[Erel]

Which type of controls do you have on your form?
For controls that support the GotFocus event you can use something like:

Sub Globals
    'Declare the global variables here.

End Sub

Sub App_Start
    Form1.Show
    AddEvent("TextBox1",GotFocus,"GotFocus")
    AddEvent("TextBox2",GotFocus,"GotFocus")
    AddEvent("TextBox3",GotFocus,"GotFocus")
End Sub

Sub GotFocus
    form1.Text = Sender
    Sender.Color = cGreen
End Sub