Take control of all TextBox

I am using ASP.NET 2.0 with Ajax


I want to get the control of all textboxes on the form and change their some properties. I use this, but it totally not working.
 
Dim myCntrl As Control
For Each myCntrl In Me.Controls
If TypeOf myCntrl Is TextBox Then
Dim txtMyTextBox As TextBox
txtMyTextBox = DirectCast(myCntrl, TextBox)
txtMyTextBox.BackColor = Drawing.Color.Red
End If
Next
 
When I run the application in debug mode, it not comming under the line
If TypeOf myCntrl Is TextBox Then
 
These textboxes either on AjaxUpdatePanel or not, same happening.
Please solve my this problem.
Thanks

 


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