用vb编写一个子程序过程,实现字符串的大小写转换,求解答

Private Sub Command1_Click()
Dim ch As String
ch = Text1.Text
___________________________
Text1.Text = ch
End Sub
Private Sub conversion(____________________)
Dim i As Integer, ch As String * 1
For i = 1 To Len(s)
ch = Mid(s, i, 1)
If ch >= "A" And ch <= "Z" Then
Mid(s, i, 1) = LCase(ch)
ElseIf ____________________Then
Mid(s, i, 1) = UCase(ch)
End If
Next i
End Sub

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Private Sub Command1_Click()
Dim ch As String
ch = Text1.Text
Call conversion(ch)
Text1.Text = ch
End Sub
Private Sub conversion(s As String)
Dim i As Integer, ch As String * 1
For i = 1 To Len(s)
ch = Mid(s, i, 1)
If ch >= "A" And ch <= "Z" Then
Mid(s, i, 1) = LCase(ch)
ElseIf ch >= "a"磨桥孝 And ch <= "消携z"瞎稿 Then
Mid(s, i, 1) = UCase(ch)
End If
Next i
End Sub

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