用VB制作计算器的问题

如果我理解没有错误的话你代码中的a是状态变量(emm...反正我是这么叫它，因为我经常这么用)，b是存储输入第一个数的变量，commond18应该是等号。
如果a=1，那么用户是想做加法运算，把变量b和当前输入的数相加
如果a=2，那么用户是想做减法运算，把变量b和当前输入的数相减
如果a=3，那么用户是想做乘法运算，把变量b和当前输入的数相乘
如果a=4，那么用户是想做除法运算，把变量b和当前输入的数相除
当然如果你的代码中commond18的那部分没有缺一个条件的话，我上面的解释就有瑕疵了

首先拖动3个文本框在右边的属性栏里把名称分别改为第一个为：text1第二个为：text2第三个为text3.
然后再拖4个控件下来分别命名：command1，command2，command3，command4
接下来就随便点一个空间输入下面的代码吧
option
explicit
private
sub
command1_click()
text3.text
=
val(text1.text)+
val(text2.text)
private
sub
command2_click()
text3.text
=
val(text1.text)-
val(text2.text)
private
sub
command3_click()
text3.text
=
val(text1.text)*
val(text2.text)
private
sub
command4_click()
text3.text
=
val(text1.text)*
val(text2.text)
end
sub

累死我了 这是我刚做的10 以下的连续计算
例如 在text1.text中输入 1-2*3 点击Command1
看看是不是能得到结果。。。

还有写地方有错误 下班了 下次再改 ！！！

Private Sub Command1_Click()
Dim b()
Dim a()
Dim n As Integer
Dim CC As String
Dim bb As String
Dim aa As Integer
Dim dd As Long
bb = Trim(Text1.Text)
aa = Len(bb)
ReDim a(aa + 2)
ReDim b(aa + 2)
For n = 1 To aa
a(n) = Mid(bb, n, 1)
Next

For n = 1 To aa
Select Case Asc(a(n))
Case 42 '*
If n <= 2 Then
a(n - 2) = "+"
End If
If n = aa - 1 Then
a(n + 2) = "+"
End If
If Asc(a(n - 2)) = 42 Or Asc(a(n - 2)) = 47 Then
If Asc(a(n + 2)) = 42 Or Asc(a(n + 2)) = 47 Then

If Asc(a(n - 2)) = 45 Then
a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) * a(n + 1)
a(n + 1) = b(n)
b(n) = 0
Else

If Asc(a(n - 2)) = 45 Then
a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) * a(n + 1)
End If
Else
If Asc(a(n + 2)) = 42 Or Asc(a(n + 2)) = 47 Then

If Asc(a(n - 2)) = 45 Then
a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) * a(n + 1)
a(n + 1) = b(n)
b(n) = 0
Else
If Asc(a(n - 2)) = 45 Then

a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) * a(n + 1)
End If

End If
Case 47 '/
If n <= 2 Then
a(n - 2) = "+"
End If
If n >= aa - 1 Then
a(n - 2) = "+"
End If

If Asc(a(n - 2)) = 42 Or Asc(a(n - 2)) = 47 Then
If Asc(a(n + 2)) = 42 Or Asc(a(n + 2)) = 47 Then

If Asc(a(n - 2)) = 45 Then
a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) / a(n + 1)
a(n + 1) = b(n)
b(n) = 0
Else

If Asc(a(n - 2)) = 45 Then
a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) / a(n + 1)
End If
Else
If Asc(a(n + 2)) = 42 Or Asc(a(n + 2)) = 47 Then

If Asc(a(n - 2)) = 45 Then
a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) / a(n + 1)
a(n + 1) = b(n)
b(n) = 0
Else

If Asc(a(n - 2)) = 45 Then
a(n - 1) = 0 - a(n - 1)
End If

b(n) = a(n - 1) / a(n + 1)
End If

End If

Case 43 '+
If n <= 2 Then
a(n - 2) = "+"
End If

If n >= aa Then
a(n + 2) = "*"
End If

If Asc(a(n - 2)) = 42 Or Asc(a(n - 2)) = 47 Then
If Asc(a(n + 2)) = 42 Or 47 Then
b(n) = 0
Else
b(n) = a(n + 1)
a(n + 1) = b(n)
b(n) = 0
End If
Else
If Asc(a(n + 2)) = 42 Or Asc(a(n + 2)) = 47 Then
b(n) = a(n - 1)
Else
b(n) = a(n - 1) + a(n + 1)
a(n + 1) = b(n)
b(n) = 0
End If
End If

Case 45 '-
If n <= 2 Then
a(n - 2) = "+"
End If
If n = aa - 1 Then
a(n + 2) = "*"
a(n + 1) = 0
End If
If Asc(a(n - 2)) = 42 Or Asc(a(n - 2)) = 47 Then
If Asc(a(n + 2)) = 42 Or Asc(a(n + 2)) = 47 Then
b(n) = 0
Else
b(n) = 0 - a(n + 1)
a(n + 1) = b(n)
b(n) = 0
End If

Else

If Asc(a(n + 2)) = 42 Or Asc(a(n + 2)) = 47 Then
b(n) = a(n - 1)
Else
b(n) = a(n - 1) - a(n + 1)
a(n + 1) = b(n)
b(n) = 0
End If
End If

Case Else
If Asc(a(n)) <= 48 And Asc(a(n)) >= 57 Then
Exit Sub
End If
End Select
Next
For n = 1 To aa
If b(n) <> "" Then
dd = dd + Val(b(n))
End If
Next
MsgBox dd
End Sub

Private Sub Form_KeyPress(KeyAscii As Integer)
'MsgBox KeyAscii
End Sub

Private Sub Form_Load()
Me.KeyPreview = True
End Sub本回答被提问者采纳

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