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  1. #1
    Join Date
    Sep 2005

    Error when trying to loop through Form Controls

    I have a current form that has some code on the Submit_Click event and I recently added a Class reference at the top to validate the controls and if they fail highlight them. But now when i run the form it fails when it runs the following code:

    Sub Submit_Click(sender As Object, e As EventArgs)
    If Page.IsValid then

    Dim myForm As Control = Page.FindControl("security")
    Dim ctl1 As Control

    For Each ctl1 In myForm.Controls
    If ctl1.GetType().ToString().Equals("System.Web.UI.WebControls.TextBox") Then
    If CType(ctl1, TextBox).text = "" Then
    AutoEmail1.Ignorefieldlist += CType(ctl1, TextBox).id+","
    CType(ctl1, TextBox).Text = "I Ran"
    End If
    End If
    Next ctl1
    End if
    End Sub

    It fails specifically on the For Each line. The error i get is:

    Object reference not set to an instance of an object.
    Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

    Is there a different way i have to write the syntax now for looping through the controls if im using a class to do some validation of them?

  2. #2
    Join Date
    Nov 2003
    Portland, OR
    Sounds like this line is failing:
    Dim myForm As Control = Page.FindControl("security")

    Are you sure that FindControl is returning a reference to your form?
    Phil Weber

    Please post questions to the forums, where others may benefit.
    I do not offer free assistance by e-mail. Thank you!

  3. #3
    Join Date
    Sep 2005
    EDIT: I fixed it, i had to add ID="myformname" to the form tag..

    Last edited by oochr1soo; 09-16-2005 at 03:43 PM.

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