'增加一个窗体.窗体中有一个按扭 
'窗体名 Form1  按扭名 Command1
'以下代码在此窗体中
Option Explicit

Private Sub Command1_Click()
  MsgBox "你单击了第" & curMsgBox & "个按扭"
End Sub

'增加一个窗体.窗体中有三个按扭 
'窗体名 Form2  按扭名 Command1 Command2  Command3
'以下代码在此窗体中

Option Explicit

Private Sub Command1_Click()
  cIndex = 1
  Unload Me
End Sub

Private Sub Command2_Click()
  cIndex = 2
  Unload Me
End Sub

Private Sub Command3_Click()
  cIndex = 3
  Unload Me
End Sub

'增加一个模块 
'模块名 Module1 
'以下代码在此模块中

Option Explicit

Public cIndex As Integer

Public Function curMsgBox() As Integer
  cIndex = 0
  Form2.Show vbModal, Form1
  curMsgBox = cIndex
End Function

Public a As String
Private Sub Command1_Click()
  Form2.Show vbModal, Me
  
  MsgBox a
End Sub

Private Sub Form_Unload(Cancel As Integer)
 Form1.a = Text1.Text
End Sub