实现根据用户名查询用户信息,要求用AJAX

<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
    <title></title>
    <meta charset="utf-8" />
     <style>
         table{
             500px;
             border: 1px solid #ccc;
             border-collapse:collapse;
         }
         table td{
              border: 1px solid #ccc;
              padding:5px;
         }
         #nav{
             450px;
             text-align:center;
         }
     </style>
    <script src="js/jquery-3.3.1.js"></script>
    <script>
        $(function () {
            $("#btn").click(function () {
                var UserName = $("#UserName").val();
                $.post("queryHandler.ashx", { "UserName": UserName }, function (data){
                    //console.log(data);
                    var stu = data.stu;
                    $("#tb").empty();
                    //如何把data显示在table上?要用DOM
                    for (i = 0; i <stu.length; i++) {
                        var html = "<tr><td>" + stu[i].UserId + "</td><td>" + stu[i].UserName + "</td><td>" + stu[i].Pwd + "</td></tr>";
                        $("#tb").append(html);
                    }
                }, "json");
            });
        });       
    </script>
</head>
<body>
    <div id="nav">
        用户名:<input type="text" name="UserName" id="UserName" />
        <input type="button" value="查询" id="btn" />
    </div>  
    <table>
        <thead>
            <tr>
                <td>UserId</td>
                <td>UserName</td>
                <td>Pwd</td>
            </tr>
        </thead>
       <tbody id="tb"></tbody>        
    </table>
</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>
    /// queryHandler 的摘要说明
    /// </summary>
    public class queryHandler : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";
            string UserName = context.Request["UserName"];
            string sql = "select UserId,UserName,Pwd from Users where UserName like '%"+@UserName+"%'";
            SqlParameter p = new SqlParameter("@UserName",UserName);
            DataTable dt= SQLHelper.ExecuteDataTable(sql, p);
            var stu = "{"stu":[";
            for(int i=0; i < dt.Rows.Count; i++)
            {
                stu +="{ "UserId":""+dt.Rows[i]["UserId"] + "" ,"UserName":"" + dt.Rows[i]["UserName"] + "", "Pwd":"" + dt.Rows[i]["Pwd"] + ""}";
                //最后一次循环不需要加逗号
                if (i!= dt.Rows.Count - 1)
                {
                    stu += ",";
                }
            }
            stu += "]}";
            context.Response.Write(stu);
           
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}
原文地址:https://www.cnblogs.com/zhang1997/p/8759534.html