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异步通信层

Posted on 2007-10-27 16:43  L.Zhang  阅读(180)  评论(0)    收藏  举报
//客户端脚本
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Use Async Communication Layer</title>
    
    <script language="javascript" type="text/javascript">    
        var webRequest = null;
    
        function sendRequest(action)
        {
            webRequest = new Sys.Net.WebRequest();
            webRequest.set_url("Handlers/Complex.ashx");
            webRequest.get_headers()["action"] = action;
            webRequest.set_body("data=" + encodeURIComponent("Hello World!"));
            webRequest.set_httpVerb("POST");
            webRequest.set_timeout(3000);
            
            webRequest.add_completed(onCompleted);
            webRequest.invoke();
        }
        
        function onCompleted(response, eventArgs)
        {
            if (response.get_aborted())
            {
                alert("Request aborted!");
            }
            else if (response.get_responseAvailable())
            {
                var statusCode = response.get_statusCode();
                if ((statusCode < 200) || (statusCode >= 300))
                {
                    alert("Error occurred!");
                }
                else
                {
                    alert(response.get_responseData());
                    // response.get_xml();
                    // response.get_object();
                    // response.getResponseHeader();
                }
            }
            else if (response.get_timedOut())
            {
                alert("Request timed out!");
            }
            else
            {
                alert("Error occurred!");
            }
        }
    </script>
</head>
<body>
    <form id="form1" runat="server">
        <asp:ScriptManager ID="ScriptManager1" runat="server" />
        
        <input type="button" value="Normal" onclick="sendRequest('normal');" />
        <input type="button" value="Error" onclick="sendRequest('error');" />
        <input type="button" value="Timeout" onclick="sendRequest('abc')" />
        <input type="button" value="Abort" onclick="webRequest.get_executor().abort()" />
    </form>
</body>
</html>

//服务器端代码
using System;
using System.Web;

public class Complex : IHttpHandler 
{
    
    public void ProcessRequest(HttpContext context)
    {
        context.Response.ContentType = "text/plain";

        string action = context.Request.Headers["action"];
        if (action == "normal")
        {
            context.Response.Write("You've sent: " + context.Request.Params["data"]);
        }
        else if (action == "error")
        {
            throw new Exception();
        }
        else
        {
            System.Threading.Thread.Sleep(5000);
        }        
    }
 
    public bool IsReusable
    {
        get
        {
            return false;
        }
    }

}