function login() {

              var userid = $("#username").val();

              var userpwd = $("#pwd").val();

            if (userid == "") {

                alert("登录失败,请输入账号");

                return;

            }

            if (userpwd == "") {

                alert("登录失败,请输入密码");

                return;

            }

            $.ajax({

                url: "/Home/Login",

                data: { userid: userid, userpwd: userpwd },

                type: "POST",

                success:

                    function (data) {

                        if (data == "ok") {

                            location.href =  "@Url.Action("Index", "Home")";

                        }

                        else {

                            alert("登录失败!");

                        }

                    }

            })

              return false;

        }