Control arrays are odd beasts in that they can have missing elements. The simplest way to iterate a control array uses this method:
Dim i As IntegerFor i = Text1.LBound To Text1.UBound ...
However, if you have holes in your array, that method tosses anerror. To avoid that eventuality, treat the array like a collection:
Dim txt As TextBoxFor Each txt In Text1txt.Text = "Hello, World!, My Index is " & txt.IndexNext txt