>Hi all,
> I use vb.net. Anyone know how do use for loop all control in form to do something?
>Thank you ~~~

There's a good example here :http://stackoverflow.com/questions/1467964/how-do-i-iterate-controls-in-a-windows-form-app
VB equivalent would be:

<System.Runtime.CompilerServices.Extension> _
Public Shared Function FindChildrenOfType(Of TChildType As Control)(currentControl As Control) As List(Of TChildType)
	Dim childList = New List(Of TChildType)()
	For Each childControl As Control In currentControl.Controls
		If TypeOf childControl Is TChildType Then
			childList.Add(DirectCast(childControl, TChildType))
		End If
		childList.AddRange(childControl.FindChildrenOfType(Of TChildType)())
	Next
	Return childList
End Function

This has the added benefit of allowing you to filter by control type if required and also to begin drilling down from any control rather than just the form....