ASP.NET ICallbackEventHandler and ASP.net Ajax updatepanel_问答_开发者

ASP.NET ICallbackEventHandler and ASP.net Ajax updatepanel

开发者 https://www.devze.com 2023-03-13 08:32 出处：网络

i would like to use ajax UpdatePanel and ICallbackEventHandler on one page. Each will handle individual part of page, they are not related to each one.

If I remove UpdatePanel, ICallbackEventHandler is working. If I remove ICallbackEventHandler, update panel is working, but they are not working altogether :(

Default.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication1._Default"
EnableEventValidation="false" %>
   <!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>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.1/jquery.min.js"></script>
</head>
<body>
<script type="text/ecmascript">
    function BootX() {
        XUpdate();
    }

    function XUpdate() {
        X_CallServer("", "");
    }

    function X_ReceiveServerData(rValue) {
        $("#a").html(rValue);
    }
</script>
<form id="form1" runat="server">
<div id="a">
</div>
<asp:ScriptManager runat="server" ID="ScriptManager1" />
<div>
    <asp:Timer ID="Timer1" runat="server" Interval="100" OnTick="Timer1_Tick">
    </asp:Timer>
    <asp:UpdatePanel runat="server" ID="UpdatePanel1" UpdateMode="Conditional">
        <ContentTemplate>
            <asp:DropDownList runat="server" ID="ddl">
            </asp:DropDownList>
        </ContentTemplat开发者_JS百科e>
    </asp:UpdatePanel>
</div>
</form>
<script type="text/ecmascript">
    BootX();
</script>
</body>
</html>

And code behind:

public partial class _Default : System.Web.UI.Page, ICallbackEventHandler
{
    protected void Page_Load(object sender, EventArgs e)
    {
        String cbReference = Page.ClientScript.GetCallbackEventReference(this, "arg", "X_ReceiveServerData", "context", true);
        String callbackScript = string.Format("function X_CallServer(arg, context)" + "{{ {0} ;}}", cbReference);
        Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "X_CallServer", callbackScript, true);
        ScriptManager1.RegisterAsyncPostBackControl(Timer1);
    }

    private string result = "";
    public void RaiseCallbackEvent(string eventArgument)
    {
        // pretending some time consuming work
        for (int i = 0; i < 1000000; i++) for (int j = 0; j < 100; j++) ;
        result = "aaaaaaaaaaaaaaaaaaaaaaaaaaaa";
    }

    public string GetCallbackResult()
    {
        return result;
    }

    protected void Timer1_Tick(object sender, EventArgs e)
    {
        UpdatePanel1.Update();
        Timer1.Enabled = false;

        // pretending some time consuming work
        for (int i = 0; i < 1000000; i++) for (int j = 0; j < 1000; j++) ;
        ddl.Items.Add("Item 1");
        ddl.Items.Add("Item 2");
        ddl.Items.Add("Item 3");
    }
}

The code above is just concept. I already have 5 control using ICallbackEventhandler on one page and they are working perfectly, now I need to add one new control to page which is using updatepanel, and it broke all of my other "ICallbackEventhandler" controls.

After few hours I found solution.

Instead of

<script type="text/ecmascript">    BootX();</script>

I used

function pageLoad(sender, args) {setTimeout("BootX()", 25); }

And it's working. The solution was quite easy :) UpdatePanel uses Postback, everytime when postback is made pageLoad method is called and here we call callback func.