Ajax 

 <script>
        $(function () {
            $("#btn").click(function () {
                var UserName=$("#UserName").val();
                var UserPwd = $("#UserPwd").val();
                if (UserName == "" || UserPwd == "") {
                    alert("用户名或密码不能为空！");
                }
                else {
                    $.get("LoginHandler.ashx", { "UserName": UserName, "UserPwd": UserPwd }, function (data) {
                        if (data == "ok") {
                            window.location.href = "main.html";
                        }
                        else {
                            alert(data);
                        }
                    })
                }              
            })
        })
    </script>

 

<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title></title>
    <meta charset="utf-8" />
    <script>
        window.onload = function () {
            function myAjax(httpMethod, url, callback) {
                //发送异步请求
                var xhr = new XMLHttpRequest();
                xhr.open(httpMethod, url, true);
                xhr.send();
                xhr.onreadystatechange = function () {
                    if (xhr.readyState == 4 && xhr.status == 200) {
                        callback(xhr.responseText);
                    }
                }
            }
            var btnLogin = document.getElementById("btn").onclick = function () {
                var UserName = document.getElementById("UserName").value;
                var UserPwd = document.getElementById("UserPwd").value;
                if (UserName == "" || UserPwd == "") {
                    alert("用户名或密码不能为空");
                }
                else {
                    var xhr = new XMLHttpRequest();
                    var strUrl = "LoginHandler.ashx?UserName=" + UserName + "&&UserPwd=" + UserPwd;
                    ////提交后台进行处理                   
                    //xhr.open("Get", strUrl,true);
                    ////使用send方法发送请求
                    //xhr.send();
                    //xhr.onreadystatechange = function () {
                    //    if (xhr.readyState == 4 && xhr.status == 200) {
                    //        if (xhr.responseText == "ok") {
                    //            window.location.href = "main.html";
                    //        }
                    //        else {
                    //            alert(xhr.responseText);
                    //        }
                    //    }
                    //}                    
                   
                    myAjax("get",strUrl,function(data){
                        if (data == "ok") {
                            window.location.href = "main.html";
                        }
                        else {
                            alert(data);
                        }
                    })
                }
            }
        }       
    </script>
</head>
<body>
    用户名：<input type="text" name="UserName" id="UserName" />
    <br />
    密&nbsp;&nbsp;码：<input type="password" name="UserPwd" id="UserPwd" />
    <br />
    <input type="button" value="登录" id="btn" />
</body>
</html>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;

namespace AJAX
{
    /// <summary>
    /// LoginHandler 的摘要说明
    /// </summary>
    public class LoginHandler : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";
            string UserName = context.Request["UserName"];
            string UserPwd = context.Request["UserPwd"];
         
            string sql = "select count(*) from Users where UserName=@u and Pwd=@p" ;
            SqlParameter[] p = { new SqlParameter("@u",UserName),
                                 new SqlParameter("@p",UserPwd),};    
            int i = Convert.ToInt32(SQLHelper.ExecuteScalar(sql,p));
            if (i == 1)
            {
                context.Response.Write("ok");
            }
            else
            {
                context.Response.Write("用户名或密码错误");
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

 

posted @ 2018-04-08 11:01  你的斗志并没有失去  阅读(191)  评论(0)    收藏  举报