情感交流篇：HTML页面如何与后端联系

通过ajax

get方法：

　　基本格式：$.get("后台一般处理程序文件路径",{传值，格式为  KEY:VULES},function(后台返回值){接到后台数据后处理});

 $.get("Ajax/ToBeAssigned.ashx?" + Math.random(), { Action: "Update", StudyNo: studyno, ExamNo: examno, DeptCode: DeptCode }, function(data) {
                 if (data != null) {
                     if (data == ) {
                         $("#tow").append("<tr style='border: 0px;background:#FFFFFF'><td colspan='7' style='border: 0px;'><label style='color: #FF0000;'>关联成功！</label></td></tr>");
                     } else {
                         $("#tow").append("<tr style='border: 0px;background:#FFFFFF'><td colspan='7' style='border: 0px;'><label style='color: #FF0000;'>关联失败！</label></td></tr>");
                     }
                 }
             });

①后台获取前台出入的值，用  context.Request["KEY"];

②后台处理（包括对数据库的增删改查）

③后台输出给前台，用context.Response.Write(result);

post方法：

　　基本格式：同get方法

①后台获取前台出入的值，用  context.Request.Form["KEY"];

②后台处理（包括对数据库的增删改查）

③后台输出给前台，用context.Response.Write(result);

 function ShowRegBox() {
     layer.open({
         type: 1,
         title: "注册",
         area: ["400px", "490px"],
         content: $("#regbox")
     });
 }

 function Reg()
 {
     var username = $("#txtRegUserName").val();
     var pwd = $.md5($("#txtRegPwd").val());
     var qq = $("#txtRegQQ").val();
     var email = $("#txtRegEmail").val();
     var tel = $("#txtRegTel").val();
     if (username == "" || pwd == "") {
         layer.msg("用户名密码不能为空！", { title: "提示", icon: 5 });
     }
     else {
         $.post("/demo.ashx", { "username": username, "pwd": pwd, "qq": qq, "email": email, "tel": tel, "cmd": "reg" }, function (data) {
             if(data=="注册成功")
             {
                 layer.msg(data, {
                     icon:6
                 });
             }
             else
             {
                 layer.msg(data, {
                     icon: 5
                 });
             }
         });
     }
 }

后台处理：

 using System;
 using System.Collections.Generic;
 using System.Data;
 using System.Data.SqlClient;
 using System.Linq;
 using System.Web;

 namespace PROJECT20160712
 {
     /// <summary>
     /// demo 的摘要说明
     /// </summary>
     public class demo : IHttpHandler
     {
         public HttpContext context;
         public string strResult = "";
         public void ProcessRequest(HttpContext context)
         {
             this.context = context;
             string cmd=context.Request.Form["cmd"];
             switch(cmd)
             {
                 case"login":
                     strResult=LoginAjax();
                     break;
                 case "reg":
                     strResult = RegAjax();
                     break;
             }
             context.Response.Write(strResult);
         }

         public string RegAjax()
         {
             string username = context.Request.Form["username"];
             string pwd = context.Request.Form["pwd"];
             string qq = context.Request.Form["qq"];
             string email = context.Request.Form["email"];
             string tel = context.Request.Form["tel"];

             string strSql = string.Format("select * from login where username='{0}'", username);
             if (SqlHelper.Exists(strSql))
             {
                 return "该用户已经被注册";
             }
             else
             {
                 //string strSql1 = string.Format("insert into login values('{0}','{1}','{2}','{3}','{4}')", pwd, username, qq, email, tel);
                 string strSql1 = "insert into login values(@pwd,@username,@qq,@email,@tel)";
                 SqlParameter[] para1 = new SqlParameter[]
                 {
                     new SqlParameter("@pwd",SqlDbType.NVarChar),
                     new SqlParameter("@username",SqlDbType.NVarChar) ,
                     new SqlParameter("@qq",SqlDbType.NVarChar),
                     new SqlParameter("@email",SqlDbType.NVarChar) ,
                     new SqlParameter("@tel",SqlDbType.NVarChar)
                 };
                 para1[].Value = pwd;
                 para1[].Value = username;
                 para1[].Value = qq;
                 para1[].Value = email;
                 para1[].Value = tel;
                 if (SqlHelper.ExecteNonQueryText(strSql1, para1) > )
                 {
                     return "注册成功";
                 }
                 else
                 {
                     return "注册失败";
                 }
             }
         }
         public string LoginAjax()
         {
             //content上下文对象，包括下面2个方法
             //Request请求、Response响应
             string username = context.Request.Form["username"];
             string pwd = context.Request.Form["pwd"];
             //string strSql = string.Format("select * from Login where username='{0}' and pwd='{1}'", username, pwd);

             string strSql = "select * from Login where username=@username and pwd=@pwd";
             SqlParameter[] para = new SqlParameter[]
             {
                 new SqlParameter("@username",SqlDbType.NVarChar),
                 new SqlParameter("@pwd",SqlDbType.NVarChar)
             };
             para[].Value = username;
             para[].Value = pwd;

             if (SqlHelper.Exists(strSql))
             {
                 return "登录成功";
             }
             else
             {
                 return "登录帐号密码不匹配";
             }
         }
         public bool IsReusable
         {
             get
             {
                 return false;
             }
         }
     }
 }