Getting a runtime exception when I add a UserControl on a page, but there are no compiler errors

Exception of type 'System.Web.HttpUnhandledException' was thrown.

Step into: Stepping over non-user code 'System.Web.UI.Control.OnLoad'
Step into: Stepping over non-user code 'System.Web.UI.Control.LoadRecursive'
Step into: Stepping over non-user code 'System.Web.UI.Control.LoadRecursive'
Step into: Stepping over non-user code 'System.Web.UI.Control.LoadRecursive'
Step into: Stepping over non-user code 'System.Web.UI.Page.开发者_开发问答ProcessRequestMain'
Step into: Stepping over non-user code 'System.Web.UI.Page.ProcessRequest'
Step into: Stepping over non-user code 'System.Web.UI.Page.ProcessRequest'
Step into: Stepping over non-user code 'System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute'
Step into: Stepping over non-user code 'System.Web.HttpApplication.ExecuteStep'
A first chance exception of type 'System.NullReferenceException' occurred in App_Code.2x2ldwnl.dll
A first chance exception of type 'System.Exception' occurred in App_Code.2x2ldwnl.dll
A first chance exception of type 'System.ServiceModel.CommunicationException' occurred in mscorlib.dll
A first chance exception of type 'System.NullReferenceException' occurred in App_Code.2x2ldwnl.dll
A first chance exception of type 'System.Exception' occurred in App_Code.2x2ldwnl.dll

My Usercontrol also compiles fine when built on its own eveything builds fine but then crash when i run debug walkthrough. any ideas what might be causing this ?

Usercontrol code:

Call Function
protected void DisplaySendMessageQuestion(string title, int messageType)
{
    UCResetPasswordDisplay.SetVisible(true);
    UCResetPasswordDisplay.MessageType = messageType.ToString();
    UCResetPasswordDisplay.Title = title;
}

User Control aspx.cs

public partial class UserControls__ResetPasswordPopup : System.Web.UI.UserControl
{
    public event EventHandler YesResetClick;
    public event EventHandler NoResetClick;


protected void Page_Load(object sender, EventArgs e)
{
    PnlAddConfirmation.CssClass = "PanelResetPass";
    PnlAddConfirmation.CssClass = "PanelYesNoCore";
    txtUsername.Focus();
}

public string MessageType
{
    get { return this.lblMessageType.Text; }
    set { this.lblMessageType.Text = value; }
}

public string UserData
{
    get { return this.txtUsername.Text; }
    set { this.txtUsername.Text = value; }
}

public string Title
{
    get { return this.lblEventTitle.Text; }
    set { this.lblEventTitle.Text = value; }
}

public bool IsVisible
{
    get { return this.PnlAddConfirmation.Visible; }
    set { this.PnlAddConfirmation.Visible = value; }
}

public string ErrorMessage
{
    get { return this.LblEventNotification.Text; }
    set { this.LblEventNotification.Text = value; }
}

public void SetVisible(bool Visible)
{
    PnlAddConfirmation.Visible = Visible;
  //  PnlScreenCover.Visible = Visible;
}

protected void ChangePasswordButton_Click(object sender, EventArgs e)
{
    if (YesResetClick != null)
    {
        YesResetClick(this, EventArgs.Empty);
    }
}
protected void ImgBtnCancel_Click(object sender, EventArgs e)
{
    if (NoResetClick != null)
    {
          NoResetClick(this, EventArgs.Empty);
        }
    }
}

Based on the code you have posted - one of the following must be true:

• PnlAddConfirmation is null
• txtUsername is null

Since the NullReferenceException is being thrown in the OnLoad method - and therefore your control's Page_Load handler.

One thing you can do is to enable break on all exceptions in VS - Open the menu: Debug -> Exceptions. In the dialog that is shown (below) make sure that the 'Thrown' checkbox is ticked.

With the debugger attached, you should get sent directly to the line of code where the error is occurring. Make sure your web.config has <compilation mode="debug"> set too, otherwise you won't have the necessary symbols for this to work correctly.

It was a validator Control pointing to validate a changed textbox name. even in debug mode as you have suggested the debugger failed to notice it. I moved the whole thing to a clean project and the debugger finally noticed it.

I was ragin, my work needs to upgrade to vs2010 and have a more less retarded VS debugger, a misspelt name should noticed as an error, being one of the most common human mistakes and all.