//解决中文乱码

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;

}

var str = toUtf8("https://www.imooc.com"); 

 $("#qrcode").qrcode(str); 

可以使用，我用了