vb设计计算器

计算器的设计 Option Explicit Dim str1 As String Dim str2 As String Dim strtemp As String Dim blnStatus As Boolean Dim intOperate As Integer Dim strtemp1 As String Private Sub cmdBack Click If Not blnStatus Then strtemp str1 Else strtemp str2 If Len strtemp 0 Then strtemp Left strtemp Len strtemp 1 txtDisplay strtemp If Not blnStatus Then str1 strtemp Else str2 strtemp End Sub Private Sub cmdmc Click cmdmstore Caption txtDisplay Text strtemp1 str1 blnStatus False End Sub Private Sub cmdmr Click txtDisplay Text strtemp1 str1 blnStatus False End Sub Private Sub cmdms Click cmdmstore Caption m strtemp1 str1 str1 blnStatus False End Sub Private Sub cmdCalc Click Index As Integer str2 txtDisplay Text blnStatus True intOperate Index End Sub Private Sub cmdEqual Click Index As Integer If Len Trim str1 0 Or Len Trim str1 0 Then blnStatus False Exit Sub End If Dim dbl1 As Double Dim dbl2 As Double dbl1 Val str1 dbl2 Val str2 Select Case intOperate Case 0 txtDisplay Text dbl1 dbl2 Case 1 txtDisplay Text dbl1 dbl2 Case 2 txtDisplay Text dbl1 dbl2 Case 3 If dbl2 0 Then MsgBox 除数不能为零 16 计算器 Exit Sub End If txtDisplay Text dbl1 dbl2 End Select blnStatus False str1 str2 End Sub Private Sub cmdM Click Index As Integer If Len Trim str1 0 Or Len Trim strtemp1 0 Then blnStatus False Exit Sub End If Dim dbl1 As Double Dim dbl2 As Double dbl1 Val str1 dbl2 Val strtemp1 strtemp1 dbl1 dbl2 If Len strtemp1 0 And Left strtemp1 1 Then strtemp 0 strtemp End If blnStatus True str1 strtemp1 str2 End Sub Private Sub cmdNumber Click Index As Integer If Not blnStatus Then strtemp str1 Else strtemp str2 If Index 1 And Left strtemp 1 0 And Mid strtemp 2 1 Then strtemp Right strtemp Len strtemp 1 End If txtDisplay Text strtemp If Not blnStatus Then str1 strtemp Else str2 strtemp End Sub Private Sub cmdPN Click If Not blnStatus Then strtemp str1 Else strtemp str2 If Len strtemp 0 And Left strtemp 1 Then strtemp Right strtemp Len strtemp 1 Else s