程序代码：

CLEAR ALL
CLEAR
Main()
CLEAR ALL
RETURN 

PROCEDURE Main()
    LOCAL loMainForm
    loMainForm = CREATEOBJECT("_MainForm")
    WITH loMainForm
        .Caption = "可滾動容器示例程序"
        .MinWidth = 800
        .MinHeight = 600
        .MaxWidth = 2000
        .MaxHeight = 1500
        .AutoCenter = .T.
        .Show
    ENDWITH
    READ EVENTS
ENDPROC 

*-----------------------------
* 定義主窗體
*-----------------------------
DEFINE CLASS _MainForm AS Form 

    ADD OBJECT Container1 AS _Container
   
    PROCEDURE Arrange
        WITH ThisForm.Container1
            .Top = 5
            .Left = 5
            .Height = ThisForm.Height - .Top - 5
            .Width = ThisForm.Width - .Left - 5
        ENDWITH
    ENDPROC
   
    PROCEDURE Activate
        ThisForm.Arrange
    ENDPROC
   
    PROCEDURE Resize
        ThisForm.Arrange
    ENDPROC 

    PROCEDURE Destroy
        CLEAR EVENTS
    ENDPROC
   
ENDDEFINE 

*-----------------------------
* 從可滾動容器基類繼承的子類，添加實際控件，響應事件和方法在基類中
*-----------------------------
DEFINE CLASS _Container AS ContainerWithScroll

    ADD OBJECT Label1 AS Label   WITH Caption = "請用鼠標向下滾動：", Height = 25, Width = 150, Top = 10, Left = 50, Alignment = 1
    ADD OBJECT Text1  AS TextBox WITH Height = 25, Width = 200, Top = 10, Left = 200
   
    ADD OBJECT Label2 AS Label   WITH Caption = "請用鼠標向上滾動：", Height = 25, Width = 150, Top = 800, Left = 50, Alignment = 1
    ADD OBJECT Text2  AS TextBox WITH Height = 25, Width = 200, Top = 800, Left = 200

ENDDEFINE 

*-----------------------------
* 可滾動容器基類
*-----------------------------
DEFINE CLASS ContainerWithScroll AS Container
   
    PROCEDURE Init
        LOCAL lnIndex
       
        WITH This
            FOR lnIndex = 1 TO .ControlCount
                WITH .Controls(lnIndex)
                    .AddProperty("Origin_Top", .Top)
                ENDWITH
            NEXT
        ENDWITH
       
    ENDPROC
   
    PROTECTED PROCEDURE MouseWheel(tnDirection, tnShift, tnXCoord, tnYCoord)
        LOCAL lnIndex
       
        WITH This
            FOR lnIndex = 1 TO .ControlCount
                WITH .Controls(lnIndex)
                    .Top = .Top + tnDirection
                    IF .Top > .Origin_Top
                        .Top = .Origin_Top
                    ENDIF
                ENDWITH
            NEXT
        ENDWITH
       
    ENDPROC
   
ENDDEFINE