[Creat0R]

Код:

#include <GUIConstantsEx.au3>
#include <WindowsConstants.au3>
#include <EditConstants.au3>

GUICreate("Input Focus Demo", 500, 300)

$Input = GUICtrlCreateInput("Модель:", 190, 250, 260, 25)
$Exit = GUICtrlCreateButton("Exit", 20, 100, 60, 20)
GUICtrlSetState(-1, $GUI_FOCUS)

GUISetState()
GUIRegisterMsg($WM_COMMAND, "WM_COMMAND")

While 1
    Switch GUIGetMsg()
        Case $GUI_EVENT_CLOSE, $Exit
            ExitLoop
    EndSwitch
WEnd

Func WM_COMMAND($hWnd, $nMsg, $wParam, $lParam)
    Local $nNotifyCode = BitShift($wParam, 16)
    Local $nID = BitAND($wParam, 0xFFFF)

    Switch $nID
        Case $Input
            Switch $nNotifyCode
                Case $EN_SETFOCUS
                    If GUICtrlRead($Input) = "Модель:" Then
                        GUICtrlSetData($Input, "")
                    EndIf
            EndSwitch
    EndSwitch

    Return $GUI_RUNDEFMSG
EndFunc

А вообще если я правильно понял, то тебе будет интересно это.

Немного улучшенная версия

Код:

#include <GUIConstantsEx.au3>
#include <EditConstants.au3>
#include <WindowsConstants.au3>

GUICreate("_GUICtrlEdit_SetDefault")

Global $EDIT_DEF_ITEMS[1][2] = [[0, 0]]

$nEdit1 = GUICtrlCreateInput("", 5, 5, 100, 20)
_GUICtrlEdit_SetDefault($nEdit1, "This is the test", 0xFFC1C1, 0x0000FF)

$nEdit2 = GUICtrlCreateInput("", 5, 30, 100, 20)
_GUICtrlEdit_SetDefault($nEdit2, "Take 2.", 0x989898)

GUICtrlCreateInput("Just a standard input", 5, 55, 200, 20)
GUICtrlSetState(-1, $GUI_FOCUS)

GUISetState()

While GUIGetMsg() <> -3
WEnd

Func _GUICtrlEdit_SetDefault($hEdit, $sDefText, $nDefColor = 0x989898, $nTextColor = 0x000000)
    If $hEdit = 0 Then
        Return SetError(1, 0, 0)
    EndIf

    If $EDIT_DEF_ITEMS[0][0] = 0 Then
        GUIRegisterMsg($WM_COMMAND, "__EDIT_DEF_WM_COMMAND")
    EndIf

    If GUICtrlRead($hEdit) = "" Then
        GUICtrlSetColor($hEdit, $nDefColor)
        GUICtrlSetData($hEdit, $sDefText)
    EndIf

    $EDIT_DEF_ITEMS[0][0] += 1
    ReDim $EDIT_DEF_ITEMS[$EDIT_DEF_ITEMS[0][0] + 1][4]

    $EDIT_DEF_ITEMS[$EDIT_DEF_ITEMS[0][0]][0] = $hEdit
    $EDIT_DEF_ITEMS[$EDIT_DEF_ITEMS[0][0]][1] = $sDefText
    $EDIT_DEF_ITEMS[$EDIT_DEF_ITEMS[0][0]][2] = $nDefColor
    $EDIT_DEF_ITEMS[$EDIT_DEF_ITEMS[0][0]][3] = $nTextColor

    Return 1
EndFunc   ;==>_GUICtrlEdit_SetDefault

Func __EDIT_DEF_WM_COMMAND($hWnd, $msgID, $wParam, $lParam)
    Local $n = __EDIT_DEF_GETINDEX(BitAND($wParam, 0xFFFF))

    If $n = -1 Then
        Return $GUI_RUNDEFMSG
    EndIf

    Local $nMsg = BitShift($wParam, 16)

    If $nMsg = $EN_SETFOCUS Then ; Gained focus (EN_SETFOCUS)
        If (GUICtrlRead($EDIT_DEF_ITEMS[$n][0]) == $EDIT_DEF_ITEMS[$n][1]) Then
            GUICtrlSetColor($EDIT_DEF_ITEMS[$n][0], $EDIT_DEF_ITEMS[$n][3])
            GUICtrlSetData($EDIT_DEF_ITEMS[$n][0], "")
        EndIf
    ElseIf $nMsg = $EN_KILLFOCUS Then ; Lost Focus (EN_KILLFOCUS)
        If GUICtrlRead($EDIT_DEF_ITEMS[$n][0]) = "" Then
            GUICtrlSetColor($EDIT_DEF_ITEMS[$n][0], $EDIT_DEF_ITEMS[$n][2])
            GUICtrlSetData($EDIT_DEF_ITEMS[$n][0], $EDIT_DEF_ITEMS[$n][1])
        EndIf
    EndIf
EndFunc   ;==>__EDIT_DEF_WM_COMMAND

Func __EDIT_DEF_GETINDEX($hEdit)
    For $i = 1 To UBound($EDIT_DEF_ITEMS) - 1
        If $EDIT_DEF_ITEMS[$i][0] = $hEdit Then
            Return $i
        EndIf
    Next

    Return -1
EndFunc   ;==>__EDIT_DEF_GETINDEX