在窗體上加入控制元件line1，然後複製下面程式碼，執行後在窗體上拖放滑鼠即可。

OptionExplicit

PrivateSubForm_Load()

Me.AutoRedraw=True

Line1.Visible=False

EndSub

PrivateSubForm_MouseDown(ButtonAsInteger,ShiftAsInteger,XAsSingle,YAsSingle)

WithLine1

.X1=X

.Y1=Y

.X2=X

.Y2=Y

.Visible=True

EndWith

EndSub

PrivateSubForm_MouseMove(ButtonAsInteger,ShiftAsInteger,XAsSingle,YAsSingle)

WithLine1

IfButton=1Then

.X2=X

.Y2=Y

EndIf

EndWith

EndSub

PrivateSubForm_MouseUp(ButtonAsInteger,ShiftAsInteger,XAsSingle,YAsSingle)

WithLine1

IfButton=1Then

.Visible=False

Line(.X1,.Y1)-(.X2,.Y2)

EndIf

EndWith

EndSub