asp.net 2.0中异步调用数据(转) - volitation

公告

今天在老外的网上发现在一篇asp.net 2.0 中异步调用的文章。。。。。
    http://fredrik.nsquared2.com/viewpost.aspx?PostID=282&showfeedback=true

按原来的代码写了一下,又不用异步试了一下,感觉调用异步稍微快一点，不过不是很明显..
可能是调用异步时,webDev.WebServe 占用内存很大的缘故(不调用异步时占用很少...)。。。。
用过的朋友谈谈....

   异步调用。。
注意设置 Async="true"

@ Page Language="C#" Async="true" AutoEventWireup="true" CodeFile="Default3.aspx.cs" Inherits="Default3" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

<title>Untitled Page</title>

</head>

<body>

<div>

BeginInvoke Thread: <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label><br />

EndInvoke Thtead: <asp:Label ID="Label2" runat="server" Text="Label"></asp:Label><br />

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns=true>

</asp:GridView>

</div>

</form>

</body>

</html>

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.Data.SqlClient;

public partial class Default3 : System.Web.UI.Page

{

private SqlCommand _command;

private SqlConnection _con;

protected void Page_Load(object sender, EventArgs e)

{

PageAsyncTask task = new PageAsyncTask(BeginInvoke, EndInvoke, EndTimeOutInvoke, null);

Page.RegisterAsyncTask(task);

}

public IAsyncResult BeginInvoke(object sender, EventArgs e, AsyncCallback cb, object extraData)

{

this._con = new SqlConnection("Asynchronous Processing=true;Data Source=JKDL-PORTAL;Initial Catalog=Northwind;Persist Security Info=True;User ID=sa;Password=111");

string sProcName = "SELECT * FROM Customers";

for (int i = 0; i < 200; i++)

{

sProcName += " UNION ALL ";

sProcName += " SELECT * FROM Customers ";

}

this._command = new SqlCommand(sProcName, this._con);

Label1.Text = System.Threading.Thread.CurrentThread.GetHashCode().ToString();

this._con.Open();

return this._command.BeginExecuteReader(cb, extraData, CommandBehavior.CloseConnection);

}

public void EndInvoke(IAsyncResult result)

{

SqlDataReader reader = this._command.EndExecuteReader(result);

if (reader != null && reader.HasRows)

{

GridView1.DataSource = reader;

GridView1.DataBind();

}

reader.Close();

Label2.Text = System.Threading.Thread.CurrentThread.GetHashCode().ToString();

}

public void EndTimeOutInvoke(IAsyncResult result)

{

if (this._con != null && this._con.State != ConnectionState.Closed)

this._con.Close();

Response.Write("TimeOut");

}

非异步时