jQury+Ajax与C#后台交换数据

-------------------------------------------jQury+Ajax调用后台方法-------------------------------------------

JS:
  function CarState(carID) {
            $.ajax({
                type: "Post",
                url: "ShowMap.aspx/GetCarState",
                //方法传参的写法一定要对，str为形参的名字  
                data: "{'carid':'" + carID + "' }",
                contentType: "application/json; charset=utf-8",
                dataType: "json",
                success: function (data) {
                    //返回的数据用data.d获取内容   
                    alert(data.d);
                }
            });
        }
后台：

using System.Web.Script.Services;
using System.Web.Services;

[WebMethod]
   public static string GetCarState(string carid)
   {
            return "Hello world!";
    }

-------------------------------------------jQuery+Ajax提交表单-------------------------------------------

HTML:

<form id="form1" class="form form-horizontal" action="Login.aspx" method="post" style="margin-left:-10px;margin-top:-10px">
                <div class="row cl" style="margin-top:60px;">              
                    <div class="formControls col-8"  style="margin-top:-5px;">
                        <input id="t_name" name="t_name" type="text" placeholder="账户" autocomplete="off" class="input-text size-L" value="" />
                    </div>
                </div>
                <div class="row cl">
                 
                    <div class="formControls col-8" style="margin-top:-5px;">
                        <input id="t_pwd" name="t_pwd" type="password" placeholder="密码" autocomplete="off" class="input-text size-L" value="" />
                    </div>
                </div>     
                <div class="row">
                    <div class="formControls col-8 col-offset-3">
                        <input id="b_submit" type="submit" class="btn btn-success radius size-L" value="登录" onclick="validate(); return false;" />

<span id="loading" class="btn btn-success radius size-L hidden">登录中...</span>          
                    </div>
                </div>         
            </form>

JS:

<script src="Scripts/jquery-1.11.3.js"></script>
 <script src="Scripts/jquery.form.js" ></script>
 <script src="Scripts/layer/layer.js"></script>

<script type="text/javascript">
    
        function validate() {
            if ($("#t_name").val() == "") {
               layer.msg("请输入账户名！");
            } else if ($("#t_pwd").val() == "") {
                layer.msg("请输入密码！");
            } else {              
                $("#form1").ajaxSubmit({
                    dataType: "json",
                    beforeSubmit: function () {
                        $("#b_submit").hide();
                        $("#loading").removeClass("hidden");
                    }, success: function (resp) {
                        if (resp.res == 1) {       //登录成功
                            window.location.href = resp.data;
                        } else {                      //登录失败
                            $("#b_submit").show();
                            $("#loading").addClass("hidden");
                            $("#t_code").val("");                   
                            layer.msg(resp.msg);
                        }
                    }, error: function (e) {  
                        $("#b_submit").show();
                        $("#loading").addClass("hidden");                                     
                    }
                });
            }
        }
        //将光标定位到用户名输入框
        window.onload = function () {
            document.getElementById("t_name").focus();
        }
    </script>

C#后台（.aspx.cs文件）

protected void Page_Load(object sender, EventArgs e)
        {

if (IsPost)
                LoginUser();
        }
        private void LoginUser()
        {
            if (IsLocalRequest && !IsRepeatPost)
            {
                string loginname = GetFormString("t_name");
                string loginpwd = GetFormString("t_pwd");
          
                if (loginname == "")
                    ResponseText(Newtonsoft.Json.JsonConvert.SerializeObject(new { res = 0, msg = "请输入用户名！" }));
                else if (loginpwd == "")
                    ResponseText(Newtonsoft.Json.JsonConvert.SerializeObject(new { res = 0, msg = "请输入密码！" }));
                   
                else
                {
                    string str = Common.Utils.MD5(loginpwd.ToLower());
                    t_member model = MemberDal.m_MemberDal.GetModel(string.Format(" mb_name = '{0}' and mb_pwd='{1}'", loginname, Common.Utils.MD5(loginpwd.ToLower())));
                    if (model != null)
                    {
                        if (model.mb_islock == 1)
                            ResponseText(Newtonsoft.Json.JsonConvert.SerializeObject(new { res = 0, msg = "无法登录，该账户被锁定！" }));
                        else
                        {
                            model.mb_logintime = DateTime.Now.ToString();
                            model.mb_loginip = Request.UserHostAddress;
                            MemberDal.m_MemberDal.Update(model);
                            Response.Cookies[":member"].Value = Common.Serialize.SerializeObject(model);
                            Response.Cookies[":member"].Expires.AddDays(1);
                            ResponseText(Newtonsoft.Json.JsonConvert.SerializeObject(new { res = 1, msg = "登录验证通过", data = "/Master.aspx" }));
                        }
                    }
                    else {
                        ResponseText(Newtonsoft.Json.JsonConvert.SerializeObject(new { res = 0, msg = "账号或密码不正确！" }));
                    
                    }
                }
            }
        }