如何基于Ajax技术实现无刷新用户登录功能？

代码如下:

// JScript 文件 function usersLogon() { var userName = document.getElementById("txtuserName").value; var password = document.getElementById("txtpassword").value; var checkCode = document.getElementById("txtCheckCode").value; var response = userControl_logon.CheckCodeIsRight(checkCode).value; if(userName == "") { document.getElementById("txtuserName").focus(); return false; } else if(password == "") { document.getElementById("txtpassword").focus(); return false; } else if(checkCode =="") { document.getElementById("txtCheckCode").focus(); return false; } else { if(response == true) { //判断用户是否存在 userControl_logon.userNameAndPasswordIsExist(userName,password,userNameIsRight); } else { alert("验证码出错"); userControl_logon.checkCodeOperaotr(refreshCheckCode); document.getElementById("txtpassword").value = ""; } } } function userNameIsRight(res) { var userName = document.getElementById("txtuserName").value; if(res.value == true) { //用户存在,但要看此用户有没有进入管理留言版权限, userControl_logon.userNameIsRight(userName,CallBack); } else { alert("用户名或密码错误"); document.getElementById("txtpassword").value = ""; OnLoad_checkCode(); } } function CallBack(res) { if(res.value == true) { hideLogon(); var url = userControl_logon.returnUrl(); if ( url.value == 404) { showDefault(); } else { document.getElementById("Url").innerHTML = '<a href="' + url.value + '">' + url.value + '</a>' } } else { alert("对不起你的权限不够"); document.getElementById("txtpassword").value = ""; OnLoad_checkCode(); } } //隐藏登录框 function hideLogon() { var element = document.getElementById("hideLogon") element.style.display = "none" } //显示返回首页 function showDefault() { var element = document.getElementById("Returndefault") element.style.display = "block" } function OnLoad_checkCode() { userControl_logon.checkCodeOperaotr(refreshCheckCode); document.getElementById("txtuserName").focus(); // return false; } ///重新得到新的验证吗 function refreshCheckCode(res) { document.getElementById("txtCheckCode").value = ""; document.getElementById("lblNumber").innerHTML = res.value; } function abce() { alert(document.getElementById("lblNumber").value) }

下面代码

using System; using System.Data; using System.Configuration; using System.Collections; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; using System.Drawing; using LHB_SQL_2005; public partial class userControl_logon : System.Web.UI.UserControl { protected void Page_Load(object sender, EventArgs e) { if (!this.IsPostBack) { AjaxPro.Utility.RegisterTypeForAjax(typeof(userControl_logon)); } } [AjaxPro.AjaxMethod] public static string checkCodeOperaotr() { string _checkCode = GeneralMethod.GenerateCheckCode(); System.Web.HttpContext.Current.Session["checkCode"] = _checkCode; //返回验证码 return _checkCode; } /// <summary> /// 判断验证是否正确 /// </summary> /// <param name="checkCode"></param> /// <returns></returns> [AjaxPro.AjaxMethod] public static bool CheckCodeIsRight(string checkCode) { string _checkCode = (string)(System.Web.HttpContext.Current.Session["checkCode"]); if (_checkCode == checkCode) { return true; } else { return false; } } /// <summary> /// 判断用户名及密码添加是否正确 /// </summary> /// <param name="userName">用户名</param> /// <param name="_password">用户名密码</param> /// <returns>bool</returns> [AjaxPro.AjaxMethod] public static bool userNameAndPasswordIsExist(string userName, string _password) { string password = GeneralMethod.ToEncryptPassword(_password); string executeString = "SELECT COUNT(*) FROM users WHERE userName = '" + userName.ToString() + "' AND password = '" + password + "'"; int count = int.Parse(GetCommand.ExecuteScalar(executeString)); if (count == 1) { System.Web.HttpContext.Current.Session["userName"] = userName; return true; } else { return false; } } /// <summary> /// 判断用户是不是有这进入管理留言版的权限 /// </summary> /// <param name="userName">用户名</param> /// <returns></returns> [AjaxPro.AjaxMethod] public static bool userNameIsRight(string userName) { string executeString = "SELECT [right] FROM role WHERE usersId = (select userNameId from users where userName = '" + userName + "')"; int count = int.Parse(GetCommand.ExecuteScalar(executeString)); if (count > 0) { return true; } else { return false; } } /// <summary> /// 返回Url值 /// </summary> /// <returns></returns> [AjaxPro.AjaxMethod] public static string returnUrl() { string url = ""; try { url = System.Web.HttpContext.Current.Session["url"].ToString(); } catch { url ="404"; } return url; } }

下面是页面代码