<input id="txt_2" maxlength="20" placeholder="密码" onfocus="Clearpwd();" password=""  class="form-control" />

//监听录入事件
    function UpdatePwd() {
        document.getElementById("txt_2").addEventListener(‘input‘, function () {
            var _this = this;
            var newPassword = _this.value;
            var oldPassword = window.decodeURIComponent(window.atob(_this.getAttribute("password")));//解密
            var deta = newPassword.length - oldPassword.length;

            var truePassword = "";
            var p = _this.selectionEnd;//光标结束时的位置

            for (var i = 0; i < newPassword.length; i++) {
                var c = newPassword.charAt(i);
                if (i < p && c != ‘●‘) {
                    truePassword += c;
                } else if (i < p && c == ‘●‘) {
                    truePassword += oldPassword.charAt(i);
                } else {
                    truePassword += oldPassword.substr(oldPassword.length - newPassword.length + p, newPassword.length - p);
                    break;
                }
            }
            newPassword = truePassword.replace(/\S/g, ‘●‘);
            _this.setAttribute(‘password‘, window.btoa(window.encodeURIComponent(truePassword)));//加密
            _this.value = newPassword;
            // 解决在win8中光标总是到input框的最后
            _this.selectionEnd = p;
            _this.selectionStart = p;
        }, false);
    }
    //获取光标事件
    function Clearpwd() {
        $("#txt_2").val("");
    }

function SaveData() {
        var name = $("#txt_1").val();
        var pwd = window.decodeURIComponent(window.atob($("#txt_2").attr("password")));//密码属性;
        var zz = /["‘<>%;)(&+]/;
        if (zz.test(name) || name == "" || zz.test(pwd) || $("#txt_2").val() == "") {
            Alert2("不能录入特殊字符且不能为空！");
            return false;
        }
        $.post("/Backstage/SaveUser", { name: name, pwd: pwd, oldid: $("#hi_rid").val() }, function (data) {
            Alert2(data);
            CloseChy2("div_addProduct");
            GetContent("");
        });
    }