#javascript let const

[izicodes]

Convert HTML to Image: A Step-by-Step Guide ✨

Do you want to turn some HTML code you've made that's on your website and have a way to convert it into an image for you to save?

Well, look no further! I too wanted to do the same thing but funny enough, there weren't any straightforward tutorials out there that could show you how! After hours of searching, I finally discovered the solution~!

This is an old tutorial I made 🐼

💛 Set your environment

Before we dive into the conversion process, I'll assume you already have your HTML code ready. What you want to learn is how to turn it into an image file. You should have a good grasp of HTML and JavaScript. For this tutorial, we'll use the following HTML code example:

We won't include the CSS code, as it doesn't affect this tutorial. The JavaScript file (script.js) at the bottom of the body element is where we'll add the functionality for the conversion.

Your page should resemble the following:

As you can see, the "Click me" button will handle the conversion. We aim to convert everything within the div.info-div into an image.

💛 Using the html2canvas JavaScript Library

The html2canvas library allows you to take screenshots of webpages and target specific elements on a screen. Here are the steps to include the library in your project:

The steps to put the library in your project:

Visit the html2canvas website for more information.

Copy the CDN link from here

and include it in a script tag in your project's head tag in the HTML file:

That's it for including the library on the HTML side. Now, let's move on to the JavaScript code.

💛 JavaScript Functionality

Here's the JavaScript code to handle the conversion:

In this code, I want to turn the whole div.info-div into an image, I put it into a variable in const div = document.querySelector(".info-div");.

I also put the button into a variable in const button = document.querySelector("button");

I added a click event listener to the button so when the user clicks the button, it will follow the code inside of the event listener!

You can find similar code like this in the documentation of the html2canvas library:

What is happening here is:

We add the div (or what the element we want to take an image of) into the html2canvas([element]).then((canvas)

Added the image file type url to a variable = const imageDataURL = canvas.toDataURL("image/png"); - You can replace the png to other image file types such as jpg, jpeg etc

Created an anchor/link tag, added the href attribute to imageDataURL

The download attribute is where we will give the default name to the image file, I added "dog.png"

Perform the click() function to the anchor tag so it starts to download the image we created

And that's it!

💛 The End

And that's it! You've successfully learned how to turn your HTML into an image. It's a great way to save and share your web content in a unique format.

If you have any questions or need further clarification, please comfortable to ask. Enjoy converting your HTML into images! 💖🐼

[codingquill]

JavaScript Fundamentals

I have recently completed a course that extensively covered the foundational principles of JavaScript, and I'm here to provide you with a concise overview. This post will enable you to grasp the fundamental concepts without the need to enroll in the course.

Prerequisites: Fundamental HTML Comprehension

Before delving into JavaScript, it is imperative to possess a basic understanding of HTML. Knowledge of CSS, while beneficial, is not mandatory, as it primarily pertains to the visual aspects of web pages.

Manipulating HTML Text with JavaScript

When it comes to modifying text using JavaScript, the innerHTML function is the go-to tool. Let's break down the process step by step:

Initiate the process by selecting the HTML element whose text you intend to modify. This selection can be accomplished by employing various DOM (Document Object Model) element selection methods offered by JavaScript ( I'll talk about them in a second )

Optionally, you can store the selected element in a variable (we'll get into variables shortly).

Employ the innerHTML function to substitute the existing text with your desired content.

Element Selection: IDs or Classes

You have the opportunity to enhance your element selection by assigning either an ID or a class:

Assigning an ID:

To uniquely identify an element, the .getElementById() function is your go-to choice. Here's an example in HTML and JavaScript:

HTML:

<button id="btnSearch">Search</button>

JavaScript:

document.getElementById("btnSearch").innerHTML = "Not working";

This code snippet will alter the text within the button from "Search" to "Not working."

Assigning a Class:

For broader selections of elements, you can assign a class and use the .querySelector() function. Keep in mind that this method can select multiple elements, in contrast to .getElementById(), which typically focuses on a single element and is more commonly used.

Variables

Let's keep it simple: What's a variable? Well, think of it as a container where you can put different things—these things could be numbers, words, characters, or even true/false values. These various types of stuff that you can store in a variable are called DATA TYPES.

Now, some programming languages are pretty strict about mentioning these data types. Take C and C++, for instance; they're what we call "Typed" languages, and they really care about knowing the data type.

But here's where JavaScript stands out: When you create a variable in JavaScript, you don't have to specify its data type or anything like that. JavaScript is pretty laid-back when it comes to data types.

So, how do you make a variable in JavaScript?

There are three main keywords you need to know: var, let, and const.

But if you're just starting out, here's what you need to know :

const: Use this when you want your variable to stay the same, not change. It's like a constant, as the name suggests.

var and let: These are the ones you use when you're planning to change the value stored in the variable as your program runs.

Note that var is rarely used nowadays

Check this out:

let Variable1 = 3; var Variable2 = "This is a string"; const Variable3 = true;

Notice how we can store all sorts of stuff without worrying about declaring their types in JavaScript. It's one of the reasons JavaScript is a popular choice for beginners.

Arrays

Arrays are a basically just a group of variables stored in one container ( A container is what ? a variable , So an array is also just a variable ) , now again since JavaScript is easy with datatypes it is not considered an error to store variables of different datatypeslet

for example :

myArray = [1 , 2, 4 , "Name"];

Objects in JavaScript

Objects play a significant role, especially in the world of OOP : object-oriented programming (which we'll talk about in another post). For now, let's focus on understanding what objects are and how they mirror real-world objects.

In our everyday world, objects possess characteristics or properties. Take a car, for instance; it boasts attributes like its color, speed rate, and make.

So, how do we represent a car in JavaScript? A regular variable won't quite cut it, and neither will an array. The answer lies in using an object.

const Car = { color: "red", speedRate: "200km", make: "Range Rover" };

In this example, we've encapsulated the car's properties within an object called Car. This structure is not only intuitive but also aligns with how real-world objects are conceptualized and represented in JavaScript.

Variable Scope

There are three variable scopes : global scope, local scope, and function scope. Let's break it down in plain terms.

Global Scope: Think of global scope as the wild west of variables. When you declare a variable here, it's like planting a flag that says, "I'm available everywhere in the code!" No need for any special enclosures or curly braces.

Local Scope: Picture local scope as a cozy room with its own rules. When you create a variable inside a pair of curly braces, like this:

//Not here { const Variable1 = true; //Variable1 can only be used here } //Neither here

Variable1 becomes a room-bound secret. You can't use it anywhere else in the code

Function Scope: When you declare a variable inside a function (don't worry, we'll cover functions soon), it's a member of an exclusive group. This means you can only name-drop it within that function. .

So, variable scope is all about where you place your variables and where they're allowed to be used.

Adding in user input

To capture user input in JavaScript, you can use various methods and techniques depending on the context, such as web forms, text fields, or command-line interfaces.We’ll only talk for now about HTML forms

HTML Forms:

You can create HTML forms using the &lt;;form> element and capture user input using various input elements like text fields, radio buttons, checkboxes, and more.

JavaScript can then be used to access and process the user's input.

Functions in JavaScript

Think of a function as a helpful individual with a specific task. Whenever you need that task performed in your code, you simply call upon this capable "person" to get the job done.

Declaring a Function: Declaring a function is straightforward. You define it like this:

function functionName() { // The code that defines what the function does goes here }

Then, when you need the function to carry out its task, you call it by name:

functionName();

Using Functions in HTML: Functions are often used in HTML to handle events. But what exactly is an event? It's when a user interacts with something on a web page, like clicking a button, following a link, or interacting with an image.

Event Handling: JavaScript helps us determine what should happen when a user interacts with elements on a webpage. Here's how you might use it:

HTML:

<button onclick="FunctionName()" id="btnEvent">Click me</button>

JavaScript:

function FunctionName() { var toHandle = document.getElementById("btnEvent"); // Once I've identified my button, I can specify how to handle the click event here }

In this example, when the user clicks the "Click me" button, the JavaScript function FunctionName() is called, and you can specify how to handle that event within the function.

Arrow functions : is a type of functions that was introduced in ES6, you can read more about it in the link below

If Statements

These simple constructs come into play in your code, no matter how advanced your projects become.

If Statements Demystified: Let's break it down. "If" is precisely what it sounds like: if something holds true, then do something. You define a condition within parentheses, and if that condition evaluates to true, the code enclosed in curly braces executes.

If statements are your go-to tool for handling various scenarios, including error management, addressing specific cases, and more.

Writing an If Statement:

if (Variable === "help") { console.log("Send help"); // The console.log() function outputs information to the console }

In this example, if the condition inside the parentheses (in this case, checking if the Variable is equal to "help") is true, the code within the curly braces gets executed.

Else and Else If Statements

Else: When the "if" condition is not met, the "else" part kicks in. It serves as a safety net, ensuring your program doesn't break and allowing you to specify what should happen in such cases.

Else If: Now, what if you need to check for a particular condition within a series of possibilities? That's where "else if" steps in. It allows you to examine and handle specific cases that require unique treatment.

Styling Elements with JavaScript

This is the beginner-friendly approach to changing the style of elements in JavaScript. It involves selecting an element using its ID or class, then making use of the .style.property method to set the desired styling property.

Example:

Let's say you have an HTML button with the ID "myButton," and you want to change its background color to red using JavaScript. Here's how you can do it:

HTML: <button id="myButton">Click me</button>

JavaScript:

// Select the button element by its ID const buttonElement = document.getElementById("myButton"); // Change the background color property buttonElement.style.backgroundColor = "red";

In this example, we first select the button element by its ID using document.getElementById("myButton"). Then, we use .style.backgroundColor to set the background color property of the button to "red." This straightforward approach allows you to dynamically change the style of HTML elements using JavaScript.

[stellarcharmconstellationclash]

here is a basic code for a #deckEditor in an online game using HTML and JavaScript:

HTML code:

```

<!DOCTYPE html>

<html>

<head>

<title>Deck Editor</title>

</head>

<body>

<h1>Deck Editor</h1>

<div id="card-list">

<h2>Card List:</h2>

<ul id="cards">

<!-- populate with cards from database or API -->

<li>Card 1</li>

<li>Card 2</li>

<li>Card 3</li>

<li>Card 4</li>

<li>Card 5</li>

<li>Card 6</li>

<li>Card 7</li>

<li>Card 8</li>

<li>Card 9</li>

<li>Card 10</li>

</ul>

</div>

<div id="deck-list">

<h2>Deck:</h2>

<ul id="deck">

<!-- display selected cards here -->

</ul>

</div>

<button id="save-btn">Save Deck</button>

<button id="clear-btn">Clear Deck</button>

<script src="deck-editor.js"></script>

</body>

</html>

```

JavaScript code:

```

// get references to all necessary elements

const cardsList = document.getElementById('cards');

const deckList = document.getElementById('deck');

const saveBtn = document.getElementById('save-btn');

const clearBtn = document.getElementById('clear-btn');

// create an array to store selected cards

let deck = [];

// function to add a card to the deck

function addCard(event) {

// get the clicked card

const card = event.target;

// check if card is already in deck

if (deck.includes(card.innerText)) {

alert('Card already in deck!');

} else {

// add card to deck array

deck.push(card.innerText);

// create a new li element for the card

const li = document.createElement('li');

li.innerText = card.innerText;

// append li to deck list

deckList.appendChild(li);

}

}

// function to remove a card from the deck

function removeCard(event) {

// get the clicked card

const card = event.target;

// remove card from deck array

deck.splice(deck.indexOf(card.innerText), 1);

// remove card from deck list

card.parentNode.removeChild(card);

}

// add event listeners to cards in card list

cardsList.addEventListener('click', addCard);

// add event listeners to cards in deck list

deckList.addEventListener('click', removeCard);

// function to save deck

function saveDeck() {

// check if deck is empty

if (deck.length === 0) {

alert('Deck is empty!');

} else {

// send deck array to server or save in database

console.log(deck);

alert('Deck saved!');

}

}

// function to clear deck

function clearDeck() {

// remove all cards from deck array

deck = [];

// remove all cards from deck list

while (deckList.firstChild) {

deckList.removeChild(deckList.firstChild);

}

}

// add event listener to save button

saveBtn.addEventListener('click', saveDeck);

// add event listener to clear button

clearBtn.addEventListener('click', clearDeck);

```

Note: This is a basic code and can be improved and customized according to your specific needs and game requirements.

[full-stack1]

Certainly! Let’s explore how to build a full-stack application using Node.js. In this comprehensive guide, we’ll cover the essential components and steps involved in creating a full-stack web application.

Building a Full-Stack Application with Node.js, Express, and MongoDB

1. Node.js: The Backbone of Our Application

Node.js is a runtime environment that allows us to run JavaScript on the server-side.

It’s built on Chrome’s V8 JavaScript engine and uses an event-driven, non-blocking I/O model, making it lightweight and efficient.

Node.js serves as the backbone of our application, providing the environment in which our server-side code will run.

2. Express.js: Simplifying Server-Side Development

Express.js is a minimal and flexible Node.js web application framework.

It provides a robust set of features for building web and mobile applications.

With Express.js, we can:

Set up middlewares to respond to HTTP requests.

Define routing rules.

Add additional features like template engines.

3. MongoDB: Storing Our Data

MongoDB is a document-oriented database program.

It uses JSON-like documents with optional schemas and is known for its flexibility and scalability.

We’ll use MongoDB to store our application’s data in an accessible and writable format.

Building Our Full-Stack Application: A Step-by-Step Guide

Setting Up the Environment:

Install Node.js:sudo apt install nodejs

Initialize a new Node.js project:mkdir myapp && cd myapp npm init -y

Install Express.js:npm install express

Creating the Server:

Create a basic Express server:const express = require('express'); const app = express(); const port = 3000; app.get('/', (req, res) => { res.send('Hello World!'); }); app.listen(port, () => { console.log(`Server running at http://localhost:${port}`); });

Defining Routes:

Define routes for different parts of our application:app.get('/user', (req, res) => { res.send('User Page'); });

Connecting to MongoDB:

Use Mongoose (a MongoDB object modeling tool) to connect to MongoDB and handle data storage.

Remember, this is just the beginning! Full-stack development involves frontend (client-side) work as well. You can use React, Angular, or other frontend libraries to build the user interface and connect it to your backend (Node.js and Express).

Feel free to explore more about each component and dive deeper into building your full-stack application! 😊 12

[dioticodes]

how to add masonry and infinite scroll to a tumblr theme

Hi, welcome. If you’re here, it’s because you want to add either Masonry, Infinite Scroll or both to your custom Tumblr theme.

Heads up, this guide requires some familiarity with HTML, CSS and Javascript as you will be editing your current theme and since all themes are different, I can't give step-by-step instructions on how to edit your exact theme.

Also, this post is best viewed on my desktop theme. Blame Tumblr for not supporting Markdown properly.

OVERVIEW

Alright, so what are we even adding? Basically, Masonry is used to display your posts in a nicely laid out grid, even if they're all different sizes. You tell it what your posts are, what you want them to fit into and it'll come up with a nice grid layout for you. Infinite Scroll is used to... infinitely scroll through posts with having to go to another page. It’s the endless scrolling of your Twitter/Instagram/whatever feed.

Now maybe you’ve already got one or the other in your theme and you’re looking to add the other one. Sounds pretty simple, yeah? It kind of is. The trouble is that Masonry and Infinite Scroll interact with each other. When you’re using Infinite Scroll, whenever you scroll down and load more posts, Masonry needs to check whether your post layout is still okay and correct it if it isn't.

PLUGINS

For the sake of this guide not getting too confusing and because they integrate so easily together, we’ll ONLY be using David DeSandro's Masonry and Infinite Scroll Javascript plugins. If you’ve got different versions of these plugins, remove them now as they may cause issues.

First, we need to add the plugins to your theme’s head:

<script src="https://unpkg.com/masonry-layout@4/dist/masonry.pkgd.min.js"></script><script src="https://unpkg.com/infinite-scroll@4/dist/infinite-scroll.pkgd.min.js"></script>

HTML

To get Masonry working, we need to know what your posts are and the container that they're in. Give your posts a class (e.g. .post) and your container an id (e.g. #posts). We can also specify additional options, such as column width and spacing between the posts. We want the layout to be responsive, so by following the example code Masonry provides, we'll create post-sizer and gutter-sizer.

To add Infinite Scroll, we need to know what the posts are (same as Masonry) and where to get the new content from - this will be the next page of posts on your blog. Tumblr lets us get that easily using pagination variables. Make sure you give the next page a class (e.g. .pagination__next), since this is where we'll be loading new posts from.

Your HTML might look something like this:

<div id="posts"> <div id="post-sizer"></div> <div id="gutter-sizer"></div> {block:Posts} <div class="post" id="{PostID}"> <div class="post-content"> {block:Text} {/block:Text} </div> </div> {/block:Posts} </div> <p id="footer"> {block:PreviousPage} <a href="{PreviousPage}">« Previous</a> {/block:PreviousPage} {block:NextPage} <a href="{NextPage}" class="pagination__next">Next »</a> {/block:NextPage} <a href="/archive">Archive</a> </p>

CSS

For the styling, we want the layout to be responsive so we'll set post-sizer and gutter-sizer to have a % width. For the rest of the styling, we'll use some of Masonry's example code again.

Your CSS might look something like this:

* { box-sizing: border-box; } #posts { width: 800px; } #posts:after { content: ''; display: block; clear: both; } #post-sizer, .post { width: 32.66%; } #gutter-sizer { width: 1%; } .post { background-color: lightgrey; margin-bottom: 10px; } .post-content { width: 100%; padding: 10px; float: left; }

JAVASCRIPT

In your theme's head, we can create a new script and set up Masonry inside it like this:

<script> window.onload = function() { var elem = document.getElementById('posts'); var msnry = new Masonry(elem, { itemSelector: '.post', percentPosition: true, columnWidth: '#post-sizer', gutter: '#gutter-sizer' }); } </script>

Then to actually get Masonry to generate a layout, we need to call it like this:

msnry.layout();

Usually, that's all you really need for Masonry but for Tumblr posts, any media embeds might take a bit of time to load. For example, Instagram embeds get taller when they're fully loaded (or at least they used to) and this can screw up the layout of your posts. To deal with this, you can add an observer that checks for any changes with media embeds and calculates a new layout if needed:

const embedObserver = new MutationObserver((m, o) => { msnry.layout(); }); embedObserver.observe(document, { childList: true, subtree: true });

Then finally, we need to set up Infinite Scroll. Remember, we're using the same posts that Masonry is changing. Since this plugin is made by the same guy who wrote Masonry, we can integrate it easily using outlayer:

let infScroll = new InfiniteScroll(elem, { path: '.pagination__next', append: '.post', outlayer: msnry });

Every time it loads a new page, it'll update the URL in your address bar. If you want to turn that off, you can add a new line to the previous codeblock, setting history to false:

let infScroll = new InfiniteScroll(elem, { path: '.pagination__next', append: '.post', history: false, outlayer: msnry });

And that should be it! The whole script should be something like this:

<script> window.onload = function() { // INITIALISE MASONRY var elem = document.getElementById('posts'); var msnry = new Masonry(elem, { itemSelector: '.post', percentPosition: true, columnWidth: '#post-sizer', gutter: '#gutter-sizer' }); // CALL MASONRY LAYOUT msnry.layout(); // CALL MASONRY LAYOUT ON EMBED LOAD const embedObserver = new MutationObserver((m, o) => { msnry.layout(); }); embedObserver.observe(document, { childList: true, subtree: true }); // INITIALISE INFINITE SCROLL let infScroll = new InfiniteScroll(elem, { path: '.pagination__next', append: '.post', history: false, outlayer: msnry }); } </script>

FINALLY...

Do keep in mind that your theme code will be different to this, so it's not a case of just copying and pasting everything directly. Remember to remove any old Masonry or Infinite Scroll plugins you already have. Your class and id names will probably be different and you may need to add certain HTML elements if you're missing them. You'll almost certainly need to tweak the styling too.

Feel free to shoot me a message if you need help or want to heckle me about the guide being outdated.

[sinchun]

Generator/randomizer tutorial

A few year ago, I made some light-hearted generators/randomizers – for example:

A friend asked me for a short tutorial on creating something like this, so I'll give it my best shot!

This tutorial is geared towards creating a simple randomizer/generator for a custom Tumblr page, so it's for HTML with a little bit of Javascript and CSS styling. Nothing fancy. (It's not even a great example of best Javascript coding practices. I will still a programming student when I coded these pages.)

A side note: I think you now have to ask Tumblr support to allow Javascript on your blog, but once that's been granted, you're good to go with this tutorial.

There are three sections to your custom HTML page:

CSS (i.e. the styling, or what the things on your page look like)

HTML (i.e. the building blocks of what you see and can interact with on the page)

Javascript (i.e. what happens when you interact with something on the page)

This tutorial will focus on the Javascript and assumes a basic understanding of how to set up an HTML page. For those of you who aren't familiar with HTML, I think this quick intro is pretty good.

Throughout this tutorial, I will use small text to refer to HTML elements and bold text to highlight Javascript terms.

I'm going to use my a/b/o scent generator (seen in the gif up top) as the example for this tutorial. I will start by saying that although I've called it a generator, it is actually a randomizer. All of the options are preset; when you use it, you are given a random option from the list—or, in this case, a random option from the specified list.

First things first: All of the Javascript for your HTML document will live inside <script></script> tags inside the body of your HTML. Conventionally, this will go below the actual HTML content of the body but transparently, I can't remember if this order actually matters or not.

1. Create an interface for the user

In the body of your HTML (before the script), create a select dropdown to display each list the user is able to choose from, a submit button, and a blank text element of a type that you don't use anywhere else on the page (I like to use h3 for this).

For simplicity's sake, this tutorial will assume that you also only have one select and one button on the page.

This is what this looks like for my scent generator:

The divs are optional but useful for styling purposes (not covered by this tutorial). Personally, I just like them for the organizational piece of mind :—)

2. Establishing your randomizer's options

Within the script you'll want to create your list (or lists) of options inside a constant. If you're using more than one list (where the user can pick which list they want an option from), your options constant should be an object, with each key corresponding to the value of an option in your HTML dropdown select (i.e. which list the user chooses). Each key's value will then be an array with all of the options you want to include in that list.

An object is denoted by { curly braces } and an array is denoted by [ square brackets ].

Every element in the array (i.e. option that the randomizer might select) should be inside quotation marks and separated by a comma.

This is what this looks like for my scent generator:

(Please excuse the shoddy indentation and the fact that I misspelled the word lavender.)

You can access an element by asking for the name of the object, followed by the key of the array you want, and finally by the index of element within the array (i.e. how far into the list the element is).

Don't forgot: Javascript starts counting index at 0, so the first element in the array has an index of 0 and the second has an index of 1.

In my example, I could access "Bong Water" by saying options[gamer][2]

You'll also want a variable to keep track of which list the user selects. Variables are denoted with "let" rather than "const" to indicate that the value will update in the future, but to start with, this should be the first item in your select as it will function as the default selection for your user – for example:

3. Letting the user update their selection

Now you have to connect your pool of options to the user interface. This is achieved by using query selectors (to pinpoint an element in your HTML doc) in combination with event listeners (so you can do something when the user interacts with said element).

You'll need one query selector for your select, and one for the button. Assuming you only have one of each in your document, you can use the very simple format of document.querySelector("") with the type of HTML element you're querying for inside the quotation marks – like so:

Then you'll want to put an event listener on each of these so you can keep track of when the user changes their selection and hits submit. This will follow the format of addEventListener("", () => {}) with the first argument (i.e. the quotation marks) being the type of event you're listening for and the second argument (i.e. () => {}) being the callback function that you want to execute when the event in the first argument happens.

In this case, we want to listen for change events on the select and for click events on the submit:

select.addEventListener("change", () => {})

submit.addEventListener("click", () => {})

A quick aside on functions: Functions can be fed variables (called arguments) and execute code upon them. These arguments are given to the function inside the parentheses before the =>, while the code to be executed upon them goes inside of the curly places on the other side of the =>.

In the case of these callback functions for the event listeners, the only argument you are allowed to use is event, which refers to the action the user takes that you are actively listening for.

For the select's callback function, we want to update that family variable we established in part 2 to the new value selected by the user. This is done by using the event argument and then accessing the changed value withe event.target.value.

For the submit's callback function, we only care about whether or not they clicked the button, so we don't need to use the event argument (so the parentheses will be empty). We can just execute code. Specifically, we want to execute code that will grab a random option from the selected list and then show that to the user.

This will be elaborated on in the next section, but here's a sneak peek with what this looks like for my scent generator:

4. Randomizing an answer and displaying it

For the sake of my sanity, we're going to create a separate function for the randomizing logic. This function will be invoked inside the callback function for the event listener on the submit. It will take one argument representing the selected list (e.g. the scent family the user selected in the dropdown) and return one option from that list.

Let's call this argument scentFamily.

The actual randomizing itself relies heavily on some of Javascript's built-in functions. Remember how in part 2, I talked about accessing an element via its index in the array it belongs to? All we're doing here is randomizing a number within the constraints of how long the given array is and then grabbing the element with that index.

Let's break it down—

Given the argument scentFamily, we can access the array within the options object with options[scentFamily]. Right now, we only care about how long this list is, which we can get with options[scentFamily].length

Math.random() is a function that will generate a random decimal between 0 and 1. Multiplying this by the length of our array will give us a random number between 0 and the index of the final element in the array, inclusive.

But to actually access an element by its index, we need a whole number, so we have to use the Math.floor() function to round the number down the nearest integer. Let's assign this value to const randomNum.

Last, we can access and return the randomly selected element with options[scentFamily][randomNum]

Put it all together:

Now, we want this function to execute when the user clicks the submit button, so we invoke it inside the submit's event listener's callback function and assign the returned value (i.e. its output, or in this case, the randomly selected element) to a new constant.

In my example, this would read as const scent = randomScent(family) where family is the value the user has selected and randomScent is the function we just wrote.

Finally, we want to show this new value to user by updating the text of the h3 I talked about all the way back in part 1. This is done by first using another another query selector to find the h3 in question—document.querySelector("h3")—and then assigning its innerText to the newly generated value.

Once again, this is what that event listener will look like:

And that's the last piece of the puzzle needed to complete your multi-list randomizer.

Conclusion

In retrospect, maybe I wrote this tutorial backwards and should've started with the randomizer function and then shown how to leverage that in a user interface.

That being said...

I hope this was helpful! If you found this confusing, feel free to drop me an ask or if we're mutuals on Twitter, you can always DM me there with questions, and I'll try to get back to you. (I might also update this tutorial if I get enough feedback about certain parts of it being Bad.)

thank u 4 coming to my ted talk :—)

[twinkskeletons]

your neocities page is so cool!!! i've been trying construct mine but tried to do the thing with javascript that you did on your blog page with the buttons and just got stuck on it. do you happen to know any tutorials on how to make it work?

ty!! i didnt really follow any one tutorial i think i just used a combo of w3schools and googling but i can give u a guide to what i did :]

so in html you want to id all ur buttons like this

<button type="button" id="buttonname"> click! </button>

and the same for your posts but with two classes one to use for all your posts generally and one for the specific category its in

<div class="post postcategory"> <p>contents</p> </div>

now in javascript you can use getElementById and getElementsByClassName to declare your variables

var buttontype1 = document.getElementById('buttonname'); const category1posts = document.getElementsByClassName('postcategory')

now you can set up the function to show and hide posts when a button is clicked!

buttontype1.onclick = function()showtype1{ for[let i=0; i<category1posts.length; i++]{ category1posts[i].style.display ="block"; }

for[let i=0; i<category2posts.length; i++]{ category2posts[i].style.display ="none"; }

}

line by line this 1. starts the function named showtype1 2. loops through all the posts in the variable category1posts (these will be the posts that have the class "postcategory" in the html) and 3. shows these posts then does the same thing for the next category of post but instead of showing them it doesnt display them :)

now you just need to repeat these steps for each of your buttons and post categories i hope this helps!!

[darklighthedgehog]

Was looking at some pixel art and realized for most people if you open them in a browser and zoom in, they're normally blurry.

So here's a little trick to fix that:

If you type the following into the address bar (dont hit enter) and save it as a bookmark:

javascript:(function pixelate() { const sheet = document.createElement('style'); sheet.innerHTML = 'img { image-rendering: pixelated; }'; document.head.appendChild(sheet); for(let i = 0; i < frames.length; ++i) { frames[i].document.head.appendChild(sheet); } })()

All you have to do afterwards is open the pixel art of choice and click the bookmark. Now the art is no longer blurry if you zoom in!

Pixel Art Before and After:

If having trouble making the bookmark just make a blank one, right click & hit edit, this should let you paste the *script* into the url spot.

[vexacarnivorous]

day 4/100 | wednesday | 17/5/23

today they wanted me to make a dubious quiz and i researched a little about javascript (for example, different keywords for local variables are var, let, and const. i also learned what a local variable is in the first place (can only be accessed from inside the same pair of curly braces/brackets), as well the existence of scope, which determines what code has access to variables.)

[codewithnazam]

30 Must-Know Questions and Answers for Every JavaScript Developer

1. What is JavaScript and what is it used for? JavaScript is a high-level, dynamic, and interpreted programming language. It’s used for front-end web development, creating interactive effects within a web page. 2. What are the differences between var, let, and const in JavaScript? var is function scoped, let and const are block scoped. var can be re-declared, let and const can’t. const can’t…

[codingquill]

Arrow Functions in JavaScript ES6

JavaScript offers two primary types of functions:

Function Declaration

As we discussed in a previous post JavaScript Fundamentals .

If you want to check out the course : Course link

Function Expression

This allows you to create anonymous functions by omitting the identifier. Most often, these anonymous functions are stored in variables, like this:

const double = function (number) { return number * 2; };

In ES6, a game-changing feature emerges: the arrow function.

The Arrow Function Magic ✨

Arrow functions introduce a concise and expressive way to define functions compared to traditional function expressions.

The basic syntax is refreshingly simple:

(parameter1, parameter2, ..., parameterN) => expression;

Here's the breakdown:

parameter1, parameter2, ..., parameterN: These are the function parameters.

expression: This is a single expression or statement to be executed, and it's implicitly returned.

Let's dive into an example:

const add = (a, b) => a + b;

In this snippet, we've created an arrow function named add that takes two parameters, a and b, and effortlessly returns their sum.

Here are some important tips and tricks when working with arrow functions:

Single Parameters: If your function takes only one parameter, you can skip the parentheses, like so:

const square = x => x * x;

Implicit Return: For single-line functions, you can automatically return the result without using the return keyword. The expression comes after the arrow =>.

Brace-Free Blocks: If your function has a single-line block, you can omit the curly braces:

const cube = x => x * x * x;

With these principles in mind, you can transform code like this:

const volumeOfAHouse = (side) => { return side * side * side; }

Into this elegant form:

const volumeOfAHouse = side => side * side * side;

Arrow functions bring brevity and readability to your code, making ES6 a game-changer in JavaScript development.

[openprogrammer]

VAR vs LET vs CONST A little reminder of how and when to use the right data container! #javascript #html #programming #css #coding #java #python #developer #programmer #webdeveloper #webdevelopment #code #coder #php #webdesign #software #softwaredeveloper #computerscience #codinglife #reactjs #technology #frontend #development #programmers #js #web #softwareengineer #programmingmemes #linux #javascriptdeveloper https://www.instagram.com/p/CnRFZPGP2j8/?igshid=NGJjMDIxMWI=

[parsinguspsmailers]

NPM Method for Address Parsing

When working with address data in JavaScript, using a Node Package Manager (NPM) library can simplify the address parsing process. These libraries provide pre-built functions that can handle diverse address formats and efficiently split them into structured components. Here’s an overview of popular NPM packages for address parsing, along with steps on how to implement them effectively.

1. Popular NPM Libraries for Address Parsing

Several NPM libraries make it easy to parse addresses:

Node-Geocoder: This library provides geocoding services, allowing you to parse an address and retrieve latitude, longitude, and other structured information.

Parse-Address: A straightforward library that breaks down address strings into components like street, city, state, and zip code.

LibPostal: A robust library that relies on machine learning to parse international addresses, ideal for applications dealing with global customer data.

2. Installing and Setting Up Address Parsing NPM Packages

To use an address parsing NPM package, you first need to install it in your Node.js project. Here’s how to get started with Parse-Address:

npm install parse-address

Once installed, you can import and use it as follows:

const parseAddress = require('parse-address');

let addressString = "123 Main St, Springfield, IL, 62701"; let parsedAddress = parseAddress.parseLocation(addressString);

console.log(parsedAddress);

This code will output a structured JSON object containing address components like street, city, state, and zip code.

3. Using LibPostal for Advanced Parsing Needs

For businesses dealing with international addresses, LibPostal is a powerful option. To install it, use:

npm install node-libpostal

After installation, you can parse addresses from various regions using machine learning-powered methods:

const libpostal = require('node-libpostal');

libpostal.parse_address("10 Downing St, London, SW1A 2AA, UK", (error, result) => { console.log(result); });

4. Choosing the Right Parsing Library

For Simple Use Cases: If you’re handling U.S.-based addresses with predictable formats, Parse-Address offers a quick and effective solution.

For Geocoding: If you need latitude and longitude, Node-Geocoder provides parsing alongside geolocation data.

For International Parsing: For businesses with global reach, LibPostal provides high accuracy across diverse address formats.

5. Advantages of Using NPM Libraries for Address Parsing

Time Efficiency: NPM libraries are pre-built and tested, so you save time on implementation.

Flexibility and Scalability: NPM libraries can easily be updated or swapped out for alternative solutions as your business needs evolve.

Cost-Effective: These libraries, many of which are open-source, provide reliable functionality without high costs.

Final Thoughts

NPM offers a variety of address parsing libraries, each with unique strengths for handling address data in JavaScript. From simple, structured addresses to complex, international data, selecting the right NPM package can significantly improve accuracy and efficiency in address management.

SITES WE SUPPORT

Parsing USPS Mailers – ​​​Wix

[gagande]

Purecode | JavaScript is determined lexically

The scope chain in JavaScript is determined lexically, meaning that the nesting of functions and blocks defines the accessible scopes. This allows inner functions to access variables from outer functions but not vice versa. ES6 introduced the let and const keywords to enable block scoping, which restricts variable visibility to the block in which they are declared, providing more predictable behavior compared to var.

[reddstrider]

i ported creep to javascript

const before = Date.now() - 1; if(Date.now() = before && isHere(this.you)){ this.you.lookInEye = !could; } this.you.type = "angel"; if((you.skin)){ cry() } if(world.beauty > 1){ const feather = 0.5; this.you.gravity.scale = feather; } this.wishes.push("special"); this.you.special = 10000; this.creep = true; this.weirdo = true; if(doingHere(this)); if(this.belong == herePostion){ this.belong = [0,0]; } this.cares = this.cares.filter(item => item !== "hurt"); this.wishes.push("control", "perfect body", "perfect soul"); if(getDistance(this.position, you.position) > 1200){ you.notice(this); } this.you.special = 10000; this.wishes.push("special"); this.creep = true; this.weirdo = true; if(doingHere(this)); if(this.belong == herePostion){ this.belong = [0,0]; } let she = this.you; she.runData.position = getObject("door"); for(let i = 0; i < 6; i++){ she.run(); } console.log(this.you.happyTriggers); console.log(this.you.wishes); this.you.special = 10000; this.wishes.push("special"); this.creep = true; this.weirdo = true; if(doingHere(this)); if(this.belong == herePostion){ this.belong = [0,0]; } if(this.belong == herePostion){ this.belong = [0,0]; }

[fabzen123]

A Comprehensive Guide to Testing with Socket.IO Tester

 Introduction

Real-time communication is becoming increasingly vital in modern web applications, powering everything from live chats to multiplayer games and real-time analytics. Among the many tools available for real-time data communication, Socket.IO stands out as a popular JavaScript library that enables seamless real-time, bidirectional event-based communication between a client and server. However, testing and debugging real-time systems is often challenging, which is where the Socket.IO Tester comes into play.

In this blog, we’ll explore what the Socket.IO Tester is, why it’s useful, and how you can use it to improve your development process. Whether you're new to Socket.IO or a seasoned developer, this guide will help you understand how to test your real-time applications efficiently.

 What is Socket.IO?

Before diving into the tester, let’s briefly cover what Socket.IO is and why it’s so widely adopted.

Socket.IO is a library that enables real-time, bidirectional, event-driven communication between web clients and servers. It builds on the WebSocket protocol but provides additional capabilities such as automatic reconnection, disconnection detection, and room support for broadcasting events to multiple clients.

Key features of Socket.IO include:

- Real-time Communication: Fast, event-driven messaging between the client and server.

- Fallback Support: If WebSockets aren’t supported by the browser, Socket.IO automatically falls back to long-polling.

- Event-Based Architecture: Events can be emitted and listened to, enabling easy message handling.

- Room and Namespace Support: Create isolated communication channels for specific groups of clients.

 What is a Socket.IO Tester?

A Socket.IO Tester online is a tool that allows you to simulate, test, and debug Socket.IO-based applications. It acts as a client that connects to your server, sending and receiving messages in real time. By doing so, developers can easily verify the communication flow between the server and client without writing actual application code.

Why is Socket.IO testing important?

- Real-time behavior is tricky to debug: Since Socket.IO facilitates real-time messaging, issues such as dropped messages, timing errors, or event handling glitches can be hard to trace.

- Connection stability: Network interruptions, client reconnections, and fallback mechanisms all need thorough testing to ensure a smooth user experience.

- Event consistency: Since Socket.IO works on an event-based system, testing ensures that all emitted events are being received as intended and in the correct order.

 How to Use Socket.IO Tester for Testing Your Application

Let’s walk through how you can use Socket.IO Tester to verify the functionality of your real-time application. While there are several tools that provide this functionality, we will be focusing on a browser-based Socket.IO Tester.

 Step 1: Setting up Your Socket.IO Server

Before using the Socket.IO tester, you need to have a basic Socket.IO server running. Below is an example of a simple Node.js-based Socket.IO server.

1. First, install Socket.IO and Express:

   ```bash

   npm install express socket.io

   ```

2. Create a `server.js` file with the following content:

   ```javascript

   const express = require('express');

   const http = require('http');

   const socketIo = require('socket.io');

   const app = express();

   const server = http.createServer(app);

   const io = socketIo(server);

   io.on('connection', (socket) => {

     console.log('A user connected');

     socket.on('message', (data) => {

       console.log('Received message:', data);

       // Echo the message back to the client

       socket.emit('message', `Server received: ${data}`);

     });

     socket.on('disconnect', () => {

       console.log('User disconnected');

     });

   });

   server.listen(3000, () => {

     console.log('Socket.IO server running on http://localhost:3000');

   });

   ```

3. Run the server:

   ```bash

   node server.js

   ```

At this point, your Socket.IO server should be running and ready to accept connections.

 Step 2: Connecting the Socket.IO Tester

Now that your server is up and running, the next step is to use the Socket.IO Tester to test the communication. Several Socket.IO testing tools are available online. For example, you can use the [Socket.IO Tester](https://amritb.github.io/socketio-client-tool/) or other tools like Postman.

Here’s how you can connect to your Socket.IO server using the tester:

1. Open the Socket.IO Tester in your web browser.

2. Enter the server URL: If you are running the server locally, use `http://localhost:3000`.

3. Connect to the server: Once the connection is successful, the tester will display a message indicating that the client has connected to the server.

4. Send and receive messages: 

   - Use the interface to send custom messages to the server.

   - The server will echo the messages back, and you will see the responses in real time.

 Step 3: Debugging Real-time Events

While connected to the Socket.IO server via the tester, you can test the real-time events that the server emits. For example:

- Test custom events: You can emit custom events from the tester interface and monitor how the server processes them. Similarly, if the server emits an event, you can see it displayed in the tester.

  Example:

  ```javascript

  // Server emits a custom event

  socket.emit('myEvent', 'Hello, Tester!');

  ```

- Check error handling: If the connection is dropped, the tester will automatically attempt to reconnect to the server. This helps in verifying the stability of your connection and how the app behaves in case of interruptions.

 Key Benefits of Using a Socket.IO Tester

Using a Socket.IO tester comes with several advantages that make it an indispensable tool in the development lifecycle:

 1. Quick Validation

Without writing an actual client-side application, you can quickly test the connection to your Socket.IO server. This is especially useful during early development stages when you want to verify the server’s behavior.

 2. Efficient Debugging

Socket.IO Testers allow you to easily send and receive custom events, helping you pinpoint any issues in real-time communication without having to launch a full application or rely on users for testing.

 3. Monitor Real-Time Communication

You can keep track of messages, events, and errors in real time, making it easier to ensure that your server and client are exchanging data as expected.

 4. Test Connection Stability

Simulate different network conditions (such as a dropped connection or reconnection) to ensure that your application gracefully handles disconnections and reconnections.

 5. Verify Event-Based Architecture

Socket.IO uses an event-based system where different events trigger different actions. With a Socket.IO tester, you can emit and listen to events to verify that all events are functioning correctly.

 Best Practices for Socket.IO Testing

- Use namespaces: If your application uses namespaces to handle different types of communication, ensure that you test each namespace separately.

- Handle reconnections gracefully: Test how your application handles connection drops and reconnections using the Socket.IO Tester.

- Verify payload structure: Ensure that the data payloads sent and received by the server and client adhere to the expected structure. A Socket.IO tester can help by showing you the raw data.

- Simulate different client types: If you are building a multi-client application (e.g., mobile and desktop clients), simulate different client behaviors in the Socket.IO Tester.

 Conclusion

Socket.IO testers provide developers with a valuable tool to test, debug, and monitor the real-time performance of their applications. Whether you’re developing a chat app, a real-time game, or a live data feed, using a Socket.IO tester simplifies the testing process and ensures your application is functioning correctly before going live.

By following the steps outlined in this guide, you’ll be able to connect to your Socket.IO server, test events, debug communication issues, and optimize your real-time communication channels. Happy testing!