There are many methods for generating QR codes. This article mainly shares with you the simple function of generating QR codes using 11 lines of simple JS code. I hope it can help you.
HTML code:
<img src="/static/imghwm/default1.png" data-src="jquery.js" class="lazy" style="max-width:90%" id="qrcode" data- style="max-width:90%" data- style="max-width:90%" data-url="https://www.baidu.com/" alt="JS code generation QR code example sharing" >
Related JS code:
/** * 生成二维码 * data-width={宽度} * data-height={高度} * data-url={链接} * @param $ele */ var generatorQRCODE = function ($ele) { $ele.hide(); var params = $ele.data(); if(!params['width'] || !params['height'] || !params['url']){ console.log('生成二维码参数错误'); return false; } var image = new Image(); var imageUrl = "http://pan.baidu.com/share/qrcode?w=" + params['width'] + "&h=" + params['height'] + "&url=" + params['url'] + ""; image.src = imageUrl; $ele.attr('src', imageUrl); $ele.show(); }; generatorQRCODE($("#qrcode"));
Let me share with you other generated 2 QR code case:
Use jquery.qrcode to generate QR code
1. First, add the jquery library file and qrcode plug-in to the page
<script type="text/javascript" ></script> <script type="text/javascript" src="jquery.qrcode.min.js"></script>
2. Add the following code to the page where the QR code needs to be displayed:
<p id="code"></p>
3. Call the qrcode plug-in. Supports two methods of canvas and table for image rendering
canvas method:
$('#code').qrcode("http://www.baidu.com"); //任意字符串
table method:
$("#code").qrcode({ render: "table", //table方式 width: 200, //宽度 height:200, //高度 text: "www.helloweba.com" //任意内容 });
4. If the generated QR code content contains text, you need to Convert the string to UTF-8
Define the conversion method:
function toUtf8(str) { var out, i, len, c; out = ""; len = str.length; for(i = 0; i < len; i++) { c = str.charCodeAt(i); if ((c >= 0x0001) && (c <= 0x007F)) { out += str.charAt(i); } else if (c > 0x07FF) { out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F)); out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F)); out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F)); } else { out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F)); out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F)); } } return out; }
Call the conversion method when generating:
var str = toUtf8("字符串测试!"); $('#code').qrcode(str);
2. Dynamically generate in the Vue-cli project 2 QR code
1. Introduce qrcode--------npm install qrcode
2. Introduce
import QRCode from 'qrcode' //定义生成二维码组件
3 in main.js. Use it when needed Introduce
import QRCode from 'qrcode' //引入生成二维码组件
into the component that generates the QR code. 4. Define the generated location in HTML and pay attention to adding the style
<template> <p id="query"> <h1 id="二维码">二维码:</h1> <canvas id="canvas"></canvas> </p> </template>
#canvas{ width: 80%!important; height: auto!important; }
5. Define the method to generate the QR code in js and call
//动态生成二维码 useqrcode(){ //生成的二维码内容,可以添加变量 this.QueryDetail='http://www.kspxzx.com/#/guard'+"?unique_code="+this.QueryDetail;var canvas = document.getElementById('canvas') QRCode.toCanvas(canvas, this.QueryDetail, function (error) { if (error) console.error(error) console.log('success!'); }) }
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phpqrcode class library generates QR code example code
php generates images with QR codes and forces download implementation Code
How to implement QR code recognition in PHP - example sharing
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