Wie kann man den Input Text per Button speichern ?

$Form1 = GUICreate("Form1", 157, 150, 192, 124)
$Input1 = GUICtrlCreateInput("Input1", 16, 32, 121, 21)
$Button1 = GUICtrlCreateButton("Button1", 32, 80, 75, 25)
GUISetState(@SW_SHOW)
While 1
$nMsg = GUIGetMsg()
Switch $nMsg
Case $GUI_EVENT_CLOSE
Exit
EndSwitch
Case $Button1
FileWrite("DerTextAusDemInput.txt" ,GUICtrlRead($Input1))
WEnd