常规的Jquery Ajax 验证登录，主要有3种服务端页面相应 ，也就是 aspx,ashx，asmx即webserivice 。 

下面分别用3种方式来（aspx，ashx，asmx）做服务端来处理 Jquery  Ajax 传过来的用户名和密码验证!

例： Login.html 请求用户名和密码验证！

    
     
    
      
            用户名
       
            
       
     密码
       
            
       
     
       
          
            
           
      
    
     

1.服务端为 AjaxLogin.aspx 页面

首先修改 $.ajax 的 Url："AjaxLogin.aspx"

protected void Page_Load(object sender, EventArgs e)        {            if (Request.Form["name"] != null && Request.Form["pwd"] != null)            {                if (Request.Form["name"].ToString().Trim() != "" && Request.Form["pwd"].ToString() != "")                {                    string name = Request.Form["name"].ToString().Trim();                    string pwd = Request.Form["pwd"].ToString();                    Response.Cookies.Clear();                                        Response.Cookies.Add(new HttpCookie("name", name)); //添加cookie                    Response.Cookies.Add(new HttpCookie("pwd",pwd));//添加密码                    Response.Write("你已经成功登录");                 }            }                   }

2. 服务端为 AjaxLoginAshx.ashx 页面  （一般处理程序）

首先修改 $.ajax 的 Url："AjaxLoginAshx.ashx"； 另：ashx以context.Response.Write 返回内容

[WebService(Namespace = "http://tempuri.org/")]    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]    public class AjaxLoginAshx : IHttpHandler    {        public void ProcessRequest(HttpContext context)        {            //context.Response.ContentType = "text/plain";            //context.Response.Write("Hello World");            if (context.Request.Form["name"] != null && context.Request.Form["pwd"] != null)            {                if (context.Request.Form["name"].ToString().Trim() != "" && context.Request.Form["pwd"].ToString() != "")                {                    string name = context.Request.Form["name"].ToString().Trim();                    string pwd = context.Request.Form["pwd"].ToString();                    context.Response.Cookies.Clear();                    context.Response.Cookies.Add(new HttpCookie("name", name));                    context.Response.Cookies.Add(new HttpCookie("pwd", pwd));                    context.Response.Write("你已经成功登录");                }                else                {                    context.Response.Write("没成功登录1");                }            }            else            {                context.Response.Write("没成功登录2");            }                }        public bool IsReusable        {            get            {                return false;            }        }

3. 服务端为 AjaxLoginAsmx.asmx页面  （SOAP方式HTTP访问,用XML返回）

   首先修改 $.ajax 的 Url："AjaxLoginAsmx.asmx/login";   注意：  / 后面是方法名

另asmx页面以return 返回内容,response.cookies.add添加cookie

/// 
    /// AjaxLoginAsmx 的摘要说明    /// 
    [WebService(Namespace = "http://tempuri.org/")]    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]    [System.ComponentModel.ToolboxItem(false)]    public class AjaxLoginAsmx : System.Web.Services.WebService    {        [WebMethod]        public string HelloWorld()        {            return "Hello World";        }        [WebMethod]        public string login()        {                       if (HttpContext.Current.Request.Form["name"] != null && HttpContext.Current.Request.Form["pwd"] != null)            {                if (HttpContext.Current.Request.Form["name"].ToString().Trim() != "" && HttpContext.Current.Request.Form["pwd"].ToString() != "")                {                    string name = HttpContext.Current.Request.Form["name"].ToString().Trim();                    string pwd = HttpContext.Current.Request.Form["pwd"].ToString();                    //HttpContext.Current.Response.Cookies.Add(new HttpCookie("name", name));                    //HttpContext.Current.Response.Cookies.Add(new HttpCookie("pwd", pwd));                    //HttpContext.Current.Response.Write("你已经成功登录");                    HttpContext.Current.Response.Cookies.Add(new HttpCookie("a", "123"));                    return "Hello World";                 }                else                {                    return "error1";                }            }            else            {                return "error2";            }        }