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DiagramWebControl The control collection cannot be modified ...

Thread ID:





109975 Jul 14,2013 11:20 AM UTC Jul 15,2013 12:35 PM UTC ASP.NET Web Forms (Classic) 2
Tags: DiagramWebControl
Igor Malkov
Asked On July 14, 2013 11:20 AM UTC


I have problem to add new page with DiagramWebControl to existing website.

When I trying to load page with diagram I get following error:


Server Error in '/' Application.

The control collection cannot be modified during DataBind, Init, Load, PreRender or Unload phases.


Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: The control collection cannot be modified during DataBind, Init, Load, PreRender or Unload phases.

Source Error:

[No relevant source lines]

Source File: c:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\b894f2a9\fbf83466\App_Web_a30c4m1s.0.cs    Line: 0

Stack Trace:

[HttpException (0x80004005): The control collection cannot be modified during DataBind, Init, Load, PreRender or Unload phases.] System.Web.UI.ControlCollection.RemoveAt(Int32 index) +9598151 System.Web.UI.ControlCollection.Clear() +40 Syncfusion.Web.UI.WebControls.Diagram.DiagramWebControl.OnUnload(EventArgs e) +646 System.Web.UI.Control.UnloadRecursive(Boolean dispose) +237 System.Web.UI.Control.UnloadRecursive(Boolean dispose) +173 System.Web.UI.Control.UnloadRecursive(Boolean dispose) +173 System.Web.UI.Page.UnloadRecursive(Boolean dispose) +23 System.Web.UI.Page.ProcessRequestCleanup() +56 System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +245 System.Web.UI.Page.ProcessRequest() +72 System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) +21 System.Web.UI.Page.ProcessRequest(HttpContext context) +58 ASP.orgchart_userorgcharttest_aspx.ProcessRequest(HttpContext context) in c:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\b894f2a9\fbf83466\App_Web_a30c4m1s.0.cs:0 System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +341 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +69

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.18033

I have tried to change application pools from integrated to classic.

When I create new web site with diagram control - everything ok.

Following aspx and cs files:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="UserOrgChartTest.aspx.cs" Inherits="OrgChart_UserOrgChart" %>

<%@ Register assembly="Syncfusion.Diagram.Web, Version=, Culture=neutral, PublicKeyToken=3d67ed1f87d44c89" namespace="Syncfusion.Web.UI.WebControls.Diagram" tagprefix="syncfusion" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">

<head runat="server">







<form id="form1" runat="server">

<syncfusion:DiagramWebControl ID="DiagramWebControl2" runat="server" Height="500px" Width="600px" />












using System;

using System.Collections.Generic;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

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





protected void Page_Load(object sender, EventArgs e)



















Igor Malkov
Replied On July 15, 2013 08:53 AM UTC


I have found the source of problem.

Need to append

<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>

Best regards.

Amsath Ali M [Syncfusion]
Replied On July 15, 2013 12:35 PM UTC

Hi Igor,


Thanks for using Syncfusion products.


We are happy to hear that the issue has been resolved by yourself. Please let us know if you require any further assistance on this.





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