Ajax轮询消息自动提示（消息盒子）

来源：互联网发布：剑网3脸型数据非法编辑：程序博客网时间：2024/04/28 03:47

经过一下午写了个消息盒子的例子，用的是ajax方式轮询读取，没有用到后台自动“推”数据的方式，效果良好。

前台的HTML代码：

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="mainTalk.aspx.cs" Inherits="wj_test.Talk.mainTalk" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head runat="server"> <title></title> <mce:script src="../Scripts/jquery-1.4.1.js" mce_src="Scripts/jquery-1.4.1.js" type="text/javascript"></mce:script> <mce:style></mce:style><style mce_bogus="1"> body { font-size: 12px; } #content { width: 200px; height: 50px; border: solid 1px #dedede; background-color: #eee; } #news { width: 200px; height: 13px; font-weight: bold; } li { height: 16px; line-height: 16px; list-style: none; color: #226B19; } a { text-decoration: none; color: #9E3423; } </style> <mce:script type="text/javascript"></mce:script></head><body> <form id="form1" runat="server"> <div id="content"> <div id="news"> </div> <ul id="info" style="margin: 0 0 0 0;" mce_style="margin: 0 0 0 0;"> </ul> </div> </form></body></html>

后台的C#代码，获取数据：

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;using System.Data.SqlClient;using System.Data;using System.Text;namespace wj_test.Talk{ public partial class Data : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (Request.QueryString["ID"] != null) { string id = Request.QueryString["ID"].ToString(); SqlConnection scn = new DB().getDB(); scn.Open(); string str = "select * from test_talk where Station=0 and ReID="+id+" order by ID desc"; SqlDataAdapter ada = new SqlDataAdapter(str, scn); DataTable dt = new DataTable(); ada.Fill(dt); scn.Close(); if (dt.Rows.Count > 0) { string json = DataTable2Json(dt); Response.Write(json); } else Response.Write("{}");//为空时返回{} 使json对象的length=0 } } public static string DataTable2Json(DataTable dt) { StringBuilder jsonBuilder = new StringBuilder(); jsonBuilder.Append("["); for (int i = 0; i < dt.Rows.Count; i++) { jsonBuilder.Append("{"); for (int j = 0; j < dt.Columns.Count; j++) { jsonBuilder.Append("/""); jsonBuilder.Append(dt.Columns[j].ColumnName); jsonBuilder.Append("/":/""); jsonBuilder.Append(dt.Rows[i][j].ToString()); jsonBuilder.Append("/","); } jsonBuilder.Remove(jsonBuilder.Length - 1, 1); jsonBuilder.Append("},"); } jsonBuilder.Remove(jsonBuilder.Length - 1, 1); jsonBuilder.Append("]"); return jsonBuilder.ToString(); } }}