VB简易计算器编程至少能实现加减乘除运算，并具有清零键、退格键等功能键

Answer 1

Dim num As String ,num1 As String
Dim Op As String
Private Sub CmdNum_Click(Index As Integer)
num=num+CmdNum(Index).Caption
Label1.Caption=num
End Sub

Private Sub CmdOp_Click(Index As Index)
num1=num
Label1.Caption=""
num=""
Op=CmdOp(Index).Caption
End Sub
Private Sub CmdEq_Click()
Select Case Op
Case "+"
num=CStr(Val(num1)+Val(num))
Case "-"
num=CStr(Val(num1)-Val(num))
Case "*"
num=CStr(Val(num1)*Val(num))
Case "/"
num=CStr(Val(num1)/Val(num))
End Select
Label1.Caption=num
End Sub
Private Sub CmdPoint_Click()
If InStr(num,".")<>0 Then
Exit Sub
Else num=num+"."
End If
Label1.Caption=num
End Sub
Private Sub CmdBack_Click()
If num<>"" Then
num=Left(num,Len(num)-1)
Label1.Caption=num
End Sub
Private Sub CmdCE_Click()
num=""
Label1.Caption=num
End Sub
Private Sub CmdC_Click()
num=""
num1=""
Label1.Caption=num
End Sub