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developedbyjk
developedbyjk

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QR Code Generator + Download QR as Image

#javascript #qrcodegenerator #api #webdev

🙋‍♂️Hello Friends!

👨‍💻So I tried building QR code Generator from input link with simple API And added the feature to Download That QR Code & Yeah🥵 faced a lot of bugs dealing with two different APIs but finally Made it🤩

Let me show you how simple it is!😉
(full code below the article)

📌Step 1
👉 We will need an input to paste our URL and a button to do work with that input

<input type="text" id="input"/>
<button onclick="generate()">Generate</button>
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👉we added generate function that will trigger JavaScript
🤾‍♂️But we need to show out output so we will create an an image

📌Step 2

\\create image element
let img = document.createElement("img");

\\select the div from html
let qr = document.querySelector(".qr-code");

\\ stick the generated image to html div
qr.appendChild(img);
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👉Okay so now 🏖
Input and button - Ready ✅
div to get output - Ready ✅

📌Step 3
👉The Third and main step is to add JavaScript code to generate QR

🚦Let get the input value from input tab

function generate(){
    let input = document.getElementById("input");
    }
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👉Next we will check if the value is inserted or not before clicking the generate button 🎯

The code will only run if there is value in input 😉

if yes!🤩
then we will search the qr img by API:🤓

👉we will use template literal to Pass Value of input that we got


https://api.qrserver.com/v1/create-qr-code/?size=180x180&data=${input.value}

👉And Boom💥 The API will do its work😎

if(input.value){
        img.src = `https://api.qrserver.com/v1/
        create-qr-code/?size=180x180&data=${input.value}`
};
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Now Let's Download Our QR 😍

👉To download our image we will use Another API FileSaver.js

📌Step 1
👉Adding the Cdn in Head of Html:

 <script src="https://cdnjs.cloudflare.com/ajax/libs/FileSaver.js/2.0.0/FileSaver.min.js" integrity="sha512-csNcFYJniKjJxRWRV1R7fvnXrycHP6qDR21mgz1ZP55xY5d+aHLfo9/FcGDQLfn2IfngbAHd8LdfsagcCqgTcQ==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>
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👉Now Lets Create Download Button :🎨

<button id="mybutton" >Download</button>
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And👀

//get the html button
let btnDownload = document.querySelector('#mybutton');
//get the html image
let imgdwn = document.querySelector('img');
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📌Step 2

👉Now Add a Event Listener that work when we click download button
So when we click it:🧐

-🐠first get the img src and set in imagePath ✅

btnDownload.addEventListener('click', () => {
//getting the src of image
    let imagePath = imgdwn.getAttribute('src');

});
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-🦐second get the img name from the url✅
eg : https://httpbin.org/image get the >>image and add + '.jpg' at end

btnDownload.addEventListener('click', () => {
//getting the src of image
    let imagePath = imgdwn.getAttribute('src');

//image format
    let fileName = getFileName(imagePath);

 //eg :saveAs("https://httpbin.org/image", "image.jpg"); 
    saveAs(imagePath, fileName);

});
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🧐so it will be image.jpg from the url to do that we will create getFileName(imagePath) Function

👉after getting the name of image (eg: image.jpg) from function
we will pass into saveAs(imagePath, fileName); 😀

function getFileName(str) {
//search '=' from url starting from end and give the output
    let gotstr = str.substring(str.lastIndexOf('=') + 1 );

    let format = ".jpg";
// return the format ie image.jpg
    return  gotstr.concat(format);
}
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Congratulation🎉✨
You Successfully🏆 Created a QR code Generator 🎀 and with Download Button😍

Full Code Below 👇

*📌 HTML 📙 *

<!DOCTYPE html>
<html>
<head>

<script src="https://cdnjs.cloudflare.com/ajax/libs/FileSaver.js/2.0.0/FileSaver.min.js" integrity="sha512-csNcFYJniKjJxRWRV1R7fvnXrycHP6qDR21mgz1ZP55xY5d+aHLfo9/FcGDQLfn2IfngbAHd8LdfsagcCqgTcQ==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>

</head>
<body>
    <div class="container">

            <div class="input-container">
                <input type="text" id="input" placeholder="Enter 
                 Url" autocomplete="off"/>
                <button onclick="generate()">Generate</button>
            </div>

        <div class="qr-code"></div>
        <button id="maindwnbtn" ><a href="#" id="mybutton" 
        download="qr">Download</a></button>

        </div>
<a href="linktr.ee/developedbyjk">@developedbyjk</a>
</body>
</html>
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*📌 CSS - if you want 😉 📗 *

@import url('https://fonts.googleapis.com/css2?family=Space+Mono&display=swap');
body{
    font-family: 'Space Mono', monospace;
    background-color: aliceblue;
}
.container{
    max-width: 400px;
    margin: 10%;
    max-height: 500px;
    padding: .2rem;
    display: flex;
    flex-direction: column;
    justify-content: space-evenly;
    background-color:aliceblue;
}
.input-container{
    display: flex;
    flex-direction: column;
}
.input-container input{
    padding: 12px;
    outline: none;
    border-radius: 5px;
    border: 2px dashed #c7c7c7;
      font-family: 'Space Mono', monospace;
}
.qr-code{
    margin-top: 100px;
    height: 200px;
    width: 200px;
     border: 2px dashed #c7c7c7;
}

.input-container button{
    padding: 0.5rem;
    height: 40px;
    color: #fff;
    font-size: 1rem;
    margin-top: .5rem;
    outline: none;
    border-radius: 90px;
    border: none;
    background-color: #332fd0;
    cursor: pointer;
      font-family: 'Space Mono', monospace;
}


#maindwnbtn{
        padding: 0.5rem;
    height: 40px;
    font-size: 1rem;
    margin-top: 80%;
    outline: none;
    border-radius: 90px;
    border: none;
    background-color: #332fd0;
    cursor: pointer;

}


#maindwnbtn a{
    color: #fff;
    text-decoration:none;
    font-family: 'Space Mono', monospace;
}
.qr-code{
    width: 100%;
    height: 180px;
    text-align: center;
}
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*📌 JavaScript 📗 *

let img = document.createElement("img");
let qr = document.querySelector(".qr-code");
qr.appendChild(img);
function generate(){
    let input = document.getElementById("input");
    if(input.value){
        input.style.borderColor = "#c7c7c7";
        img.src = `https://api.qrserver.com/v1/create-qr-code/?size=180x180&data=${input.value}`;

    }
    else{
        input.style.borderColor="red";
        return false;
    }
    input.value = "";


}


let btnDownload = document.querySelector('#mybutton');
let imgdwn = document.querySelector('img');



btnDownload.addEventListener('click', () => {
    let imagePath = imgdwn.getAttribute('src');
    let fileName = getFileName(imagePath);
    saveAs(imagePath, fileName);
});

function getFileName(str) {
    let gotstr = str.substring(str.lastIndexOf('=') + 1 );
    let format = ".jpg";
    return  gotstr.concat(format);
}
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Wait 😳
You reached so Below 🤯 I can't Believe it

You seem great Diver 😍😉

So Hi👋 My diver Friend👨
Myself JK 👨‍💻
I share Stuff Related to Web Design & Development
If you like this😄

I'm Sure you'll Love My Instagram Page Where I share the same,but with Visual Taste.🤝😎👀

Hope we meet There😉🎀🏝

Happy Coding 💪✨🎉

My All Links linktr.ee/developedbyjk

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