想在VB中设计一个类似卡西欧fx-82MS的双行显示的计算器程序（输入与输出在两个Text中进行），请给个思路。

每当有一个关键点时都编一个Sub
复杂的就用Function
如按“＋”时
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Import...
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Class...

'Microsoft Visual Studio 2005 Professional
'Microsoft Visual Basic 2005

Dim Addtion1 As Decimal
Dim Addtion2 As Decimal
Dim Doing As String
Dim...
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Private Sub Add.Click(ByVal....)Handle Add.Click
Doing = "Add"
Addtion1 = TextBox1.Text
Textbox1.Text = ""
End Sub

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Private Sub Equal.Click(ByVal....)Handle Equal.Click
If Doing = "Add" Then
Addtion2 = Textbox1.Text
Textbox2.Text = Addtion1 + Addtion2
ElseIf Doing = "Minus" Then
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End If
Addtion1 = 0
Addtion2 = 0
Textbox1.Text = ""
Doing = ""
End Sub
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