Git is a distributed version control system DVCS designed for efficient source code management, suitable for both small and large projects. It allows multiple developers to work on a project simultaneously without overwriting changes, supporting collaborative work, continuous integration, and deployment. This Git and GitHub tutorial is designed for beginners to learn fundamentals and advanced concepts, including branching, pushing, merging conflicts, and essential Git commands. Prerequisites include familiarity with the command line interface CLI, a text editor, and basic programming concepts. Git was developed by Linus Torvalds for Linux kernel development and tracks changes, manages versions, and enables collaboration among developers. It provides a complete backup of project history in a repository. GitHub is a hosting service for Git repositories, facilitating project access, collaboration, and version control. The tutorial covers topics such as Git installation, repository creation, Git Bash usage, managing branches, resolving conflicts, and working with platforms like Bitbucket and GitHub. The text is a comprehensive guide to using Git and GitHub, covering a wide range of topics. It includes instructions on working directories, using submodules, writing good commit messages, deleting local repositories, and understanding Git workflows like Git Flow versus GitHub Flow. There are sections on packfiles, garbage collection, and the differences between concepts like HEAD, working tree, and index. Installation instructions for Git across various platforms Ubuntu, macOS, Windows, Raspberry Pi, Termux, etc. are provided, along with credential setup. The guide explains essential Git commands, their usage, and advanced topics like debugging, merging, rebasing, patch operations, hooks, subtree, filtering commit history, and handling merge conflicts. It also covers managing branches, syncing forks, searching errors, and differences between various Git operations e.g., push origin vs. push origin master, merging vs. rebasing. The text provides a comprehensive guide on using Git and GitHub. It covers creating repositories, adding code of conduct, forking and cloning projects, and adding various media files to a repository. The text explains how to push projects, handle authentication issues, solve common Git problems, and manage repositories. It discusses using different IDEs like VSCode, Android Studio, and PyCharm, for Git operations, including creating branches and pull requests. Additionally, it details deploying applications to platforms like Heroku and Firebase, publishing static websites on GitHub Pages, and collaborating on GitHub. Other topics include the use of Git with R and Eclipse, configuring OAuth apps, generating personal access tokens, and setting up GitLab repositories. The text covers various topics related to Git, GitHub, and other version control systems Key Pointers Git is a distributed version control system DVCS for source code management. Supports collaboration, continuous integration, and deployment. Suitable for both small and large projects. Developed by Linus Torvalds for Linux kernel development. Tracks changes, manages versions, and provides complete project history. GitHub is a hosting service for Git repositories. Tutorial covers Git and GitHub fundamentals and advanced concepts. Includes instructions on installation, repository creation, and Git Bash usage. Explains managing branches, resolving conflicts, and using platforms like Bitbucket and GitHub. Covers working directories, submodules, commit messages, and Git workflows. Details packfiles, garbage collection, and Git concepts HEAD, working tree, index. Provides Git installation instructions for various platforms. Explains essential Git commands and advanced topics debugging, merging, rebasing. Covers branch management, syncing forks, and differences between Git operations. Discusses using different IDEs for Git operations and deploying applications. Details using Git with R, Eclipse, and setting up GitLab repositories. Explains CI/CD processes and using GitHub Actions. Covers internal workings of Git and its decentralized model. Highlights differences between Git version control system and GitHub hosting platform.
QR Code Generator in JavaScript with Source Codes
To create QR Code Generator in JavaScript. First, you need to create three Files: HTML, CSS & JavaScript File. After creating these files just paste the given codes into your file. You can also download the source code files of this QR Code Generator App from the below download button. First, create an HTML file with the name index.html and paste the given codes into your HTML file. Remember, you’ve to create a file with .html extension.
<!DOCTYPE html>
<!-- Coding By Codegyan - www.codegyan.in-->
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8">
<title>QR Code Generator in JavaScript | Codegyan</title>
<link rel="stylesheet" href="style.css">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>
<body>
<div class="wrapper">
<header>
<h1>QR Code Generator</h1>
<p>Paste a url or enter text to create QR code</p>
</header>
<div class="form">
<input type="text" spellcheck="false" placeholder="Enter text or url">
<button>Generate QR Code</button>
</div>
<div class="qr-code">
<img src="" alt="qr-code">
</div>
</div>
<script src="script.js"></script>
</body>
</html>
CSS
Second, create a CSS file with the name style.css and paste the given codes in your CSS file. Remember, you’ve to create a file with .css extension.
/* Import Google Font - Poppins */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;500;600;700&display=swap');
*{
margin: 0;
padding: 0;
box-sizing: border-box;
font-family: 'Poppins', sans-serif;
}
body{
display: flex;
padding: 0 10px;
min-height: 100vh;
align-items: center;
background: #3498DB;
justify-content: center;
}
.wrapper{
height: 265px;
max-width: 410px;
background: #fff;
border-radius: 7px;
padding: 20px 25px 0;
transition: height 0.2s ease;
box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}
.wrapper.active{
height: 530px;
}
header h1{
font-size: 21px;
font-weight: 500;
}
header p{
margin-top: 5px;
color: #575757;
font-size: 16px;
}
.wrapper .form{
margin: 20px 0 25px;
}
.form :where(input, button){
width: 100%;
height: 55px;
border: none;
outline: none;
border-radius: 5px;
transition: 0.1s ease;
}
.form input{
font-size: 18px;
padding: 0 17px;
border: 1px solid #999;
}
.form input:focus{
box-shadow: 0 3px 6px rgba(0,0,0,0.13);
}
.form input::placeholder{
color: #999;
}
.form button{
color: #fff;
cursor: pointer;
margin-top: 20px;
font-size: 17px;
background: #3498DB;
}
.qr-code{
opacity: 0;
display: flex;
padding: 33px 0;
border-radius: 5px;
align-items: center;
pointer-events: none;
justify-content: center;
border: 1px solid #ccc;
}
.wrapper.active .qr-code{
opacity: 1;
pointer-events: auto;
transition: opacity 0.5s 0.05s ease;
}
.qr-code img{
width: 170px;
}
@media (max-width: 430px){
.wrapper{
height: 255px;
padding: 16px 20px;
}
.wrapper.active{
height: 510px;
}
header p{
color: #696969;
}
.form :where(input, button){
height: 52px;
}
.qr-code img{
width: 160px;
}
}
const wrapper = document.querySelector(".wrapper"),
qrInput = wrapper.querySelector(".form input"),
generateBtn = wrapper.querySelector(".form button"),
qrImg = wrapper.querySelector(".qr-code img");
let preValue;
generateBtn.addEventListener("click", () => {
let qrValue = qrInput.value.trim();
if(!qrValue || preValue === qrValue) return;
preValue = qrValue;
generateBtn.innerText = "Generating QR Code...";
qrImg.src = `https://api.qrserver.com/v1/create-qr-code/?size=200x200&data=${qrValue}`;
qrImg.addEventListener("load", () => {
wrapper.classList.add("active");
generateBtn.innerText = "Generate QR Code";
});
});
qrInput.addEventListener("keyup", () => {
if(!qrInput.value.trim()) {
wrapper.classList.remove("active");
preValue = "";
}
});