Private Sub Command1_Click()
Form1.Caption = "大小写字母转换"
Label1.Caption = "输入字符串："
Label2.Caption = "转换："
Command1.Caption = "清屏"
Command2.Caption = "结束"
Text1.Text = ""
Text2.Text = ""
End Sub

Private Sub Command2_Click()
End
End Sub

Private Sub Text1_KeyPress(Keyascii As Integer)
Dim s As String * 1
Dim L As Integer         'L存放文本框中字符串的长度
L = Len(Text2.Text)      '求Text2中字符串的长度
s = Chr$(Keyascii)       '将ASCII转换成字符
Select Case s
  Case "A" To "Z"        '大写转换成小写
    s = Chr$(Keyascii + 32)
  Case "a" To "z"        '小写转换成大写
    s = Chr$(Keyascii - 32)
  Case Else
    s = "*"              '其他转换成*
End Select
    Text2.Text = Text2.Text & s
End Sub