Recursive function in Asp.Net

An important programming technique is the Recursion.
Recursive is a procedure or subroutines that contains a statement that calls itself.

In this simple example I use a recursive function to clean all TextBox even those within a container (ascx control)

Private Function CleanAll(ByVal container As Control) As ArrayList

     Dim txt As TextBox
     For Each c As Control In container.Controls
         If c.GetType.Name = "TextBox" Then
             txt = c
             If txt.Text <> "" Then
                 txt.Text = ""
                 allControlls.Add(c)
             End If
         Else
             CleanAll(c) ' invokes recursively the method
             'to add more controls in the control children
         End If
     Next
     Return allControlls

 End Function

There are two ascx controls nested one inside the other.
The same thing works with panels and other asp.net containers.
If you want, you can download this example here (visual basic) or here (c#).

For more info try here and here.

That's all !