'分割区的宽度
Private Const SPLITTERWIDTH = 45
'最小移动宽度
Private Const HMIN = 15
'picLeft和picRight的宽度相对于窗体的比例
Private Percent As Single
'正在拖动的标志
Private DragFlag As Boolean

'每次拖动后需要重排窗体上的控件
Private Sub RedrawMe()
Dim NewWidth As Single
' 忽略窗体缩小的情况
If WindowState = vbMinimized Then Exit Sub
NewWidth = (ScaleWidth - SPLITTERWIDTH) * Percent
Picleft.Move 0, 0, NewWidth, ScaleHeight
Picright.Move NewWidth + SPLITTERWIDTH, 0, ScaleWidth - NewWidth - SPLITTERWIDTH, ScaleHeight
End Sub

Private Sub Form_Load()
'PicLeft和PicRight的MousePointer=1
Percent = 0.5
End Sub

Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
DragFlag = True
End Sub

Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
'定义鼠标为vbSizeWE型
MousePointer = vbSizeWE
Percent = X / ScaleWidth
RedrawMe
End Sub

Private Sub Form_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
DragFlag = False
MousePointer = 0 '此行语句实际没有起作用
End Sub