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#include <ButtonConstants.au3>
#include <EditConstants.au3>
#include <GUIConstantsEx.au3>
#include <WindowsConstants.au3>
$Form1 = GUICreate("Form1", 223, 185, 192, 124)
$_i = GUICtrlCreateInput("", 16, 16, 193, 21)
$_1 = GUICtrlCreateButton("1", 16, 48, 35, 33)
$_2 = GUICtrlCreateButton("2", 56, 48, 35, 33)
$_3 = GUICtrlCreateButton("3", 96, 48, 35, 33)
$_4 = GUICtrlCreateButton("4", 136, 48, 35, 33)
$_5 = GUICtrlCreateButton("5", 176, 48, 35, 33)
$_6 = GUICtrlCreateButton("6", 16, 88, 35, 33)
$_7 = GUICtrlCreateButton("7", 56, 88, 35, 33)
$_8 = GUICtrlCreateButton("8", 96, 88, 35, 33)
$_9 = GUICtrlCreateButton("9", 136, 88, 35, 33)
$_10 = GUICtrlCreateButton("=", 176, 136, 35, 33)
$_11 = GUICtrlCreateButton("+", 16, 136, 35, 33)
$_12 = GUICtrlCreateButton("-", 56, 136, 35, 33)
$_13 = GUICtrlCreateButton("*", 96, 136, 35, 33)
$_14 = GUICtrlCreateButton("/", 136, 136, 35, 33)
GUISetState(@SW_SHOW)
While 1
$nMsg = GUIGetMsg()
Switch $nMsg
Case $GUI_EVENT_CLOSE
Exit
Case $_1
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "1")
Case $_2
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "2")
Case $_3
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "3")
Case $_4
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "4")
Case $_5
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "5")
Case $_6
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "6")
Case $_7
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "7")
Case $_8
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "8")
Case $_9
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "9")
Case $_10
$read = GUICtrlRead($_i)
MsgBox(0,"Ergebnis:",Execute($read))
Case $_11
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "+")
Case $_12
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "-")
Case $_13
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "*")
Case $_14
$read = GUICtrlRead($_i)
GUICtrlSetData($_i,$read & "/")
Exit
EndSwitch
WEnd