Ajax实现DataGrid/DataList动态ToolTip

1.建立一aspx页面，html代码2.cs代码

using System.Data.SqlClient;
using System.IO;
protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            BindData();
           
        }
        if (ID != "")
        {
            GetDescriptionByID(ID);
        }
       
    }

    property#region property
    private string ID
    {
        get
        {
            if (Request["ID"] != null && Request["ID"].ToString() != "")
            {
                return Request["ID"];
            }
            else
            {
                return "";
            }
        }
    }
    #endregion

    GetDescriptionByID#region GetDescriptionByID
    private void GetDescriptionByID(string ID)
    {
        string connStr = ConfigurationSettings.AppSettings["ConnectionString"];
        SqlConnection conn = new SqlConnection(connStr);
        string sql = "select * from testimage where userid=''" + ID + "''";
        SqlCommand cmd = new SqlCommand(sql, conn);
        conn.Open();
        SqlDataReader dr = cmd.ExecuteReader();

        string s = @"<table cellspacing=''0'' cellpadding=''4'' width=''300'' height=''200'' border=''0'' id=''GridView1'' style=''color:#333333;border-collapse:collapse;''>";
        if(dr.Read())
        {
            s += "<tr style=''color:#333333;background-color:#FFFBD6;''>";
            s += "<td width=''50''>名称:</td>";