Javascript前端获取扫码枪扫描到的内容方法（区分键盘输入和扫码器输入内容）

• Javascript前端获取扫码枪扫描到的内容方法（区分键盘输入和扫码器输入内容）；
• 对获取到的字符串进行特定位置字符串的提取

 window.onload = function () {// 获取扫描的二维码
        var code = "";
        var idInfo="";
        var pwdInfo="";
        var lastTime, nextTime;
        var lastCode, nextCode;
        // console.log('data'+data);
        document.onkeypress = function (e) {
            nextCode = e.which;
            nextTime = new Date().getTime();

            if (lastCode != null && lastTime != null && nextTime - lastTime <= 30) {// 扫码枪
                code += String.fromCharCode(lastCode);
            } else if (lastCode != null && lastTime != null && nextTime - lastTime > 100) { // 键盘
                code = "";
            }

            lastCode = nextCode;
            lastTime = nextTime;
        }
        this.Template_rendering = function () {
            this.onkeypress = function (e) {
                if (e.which == 13) {
                    idInfo= code.substring(code.indexOf("Id=")+7, code.lastIndexOf("p"));
                    ;//获取字符串中id=后，到p之前的数据
                    console.log("userId"+idInfo);
                    code = "";
                }
            }
        }
        this.Template_rendering();
    };