js生成网页地址二维码

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="ko" lang="ko">
<head>
<title>Javascript 二维码生成库：QRCode</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no" />
<script type="text/javascript" src="//cdn.staticfile.org/jquery/2.1.1/jquery.min.js"></script>
<script type="text/javascript" src="//static.runoob.com/assets/qrcode/qrcode.min.js"></script>
</head>
<body>
<input id="text" type="text" value="http://www.runoob.com" style="80%" /><br />
<div id="qrcode" style="100px; height:100px; margin-top:15px;"></div>

<script type="text/javascript">
var qrcode = new QRCode(document.getElementById("qrcode"), {
    width : 100,
    height : 100
});

function makeCode () {        
    var elText = document.getElementById("text");
    
    if (!elText.value) {
        alert("Input a text");
        elText.focus();
        return;
    }
    
    qrcode.makeCode(elText.value);
}

makeCode();

$("#text").
    on("blur", function () {
        makeCode();
    }).
    on("keydown", function (e) {
        if (e.keyCode == 13) {
            makeCode();
        }
    });
</script>
</body>
</html>
官网
http://davidshimjs.github.io/qrcodejs/