Example:
' Create a LINQ query.
Dim textBoxQuery = From control In Me.Controls Where TypeOf (control) Is TextField
' Create a list of object.
Dim textBoxList = textBoxQuery.ToList
' Iterate through the objects in textBoxList.
For Each txtBox As TextBox In testBoxList
' Show each TextBox's text property.
MessageBox.Show(txtBox.Text)
Next