vb计算器源代码

Option Explicit

Private StoredValue As Double

Private Const opNone = 0
Private Const opAdd = 1
Private Const opSubtract = 2
Private Const opMultiply = 3
Private Const opDivide = 4
Private Operator As Integer

Private NewEntry As Boolean

'删除最后的字符
Private Sub DeleteCharacter()
Dim txt As String
Dim min_len As Integer

txt = txtDisplay.Text
If Left$(txt, 1) = "-" Then
min_len = 2
Else
min_len = 1
End If

If Len(txt) > min_len Then
txtDisplay.Text = Left$(txt, Len(txt) - 1)
Else
txtDisplay.Text = "0"
End If
End Sub

'清除显示内容，保存运算符
Private Sub cmdClear_Click()
cmdClearEntry_Click
StoredValue = 0
Operator = opNone
End Sub

'清除显示内容
Private Sub cmdClearEntry_Click()