的小程序计算器

1、VB6.0的小程序 计算器对于刚入门学习VB6的朋友来说肯定会做些小程序吧，这里就是给大家演示个简单的计算器程序，仅供参考啦。界面上加减乘除四个按钮分别是cmdAdd、cmdPlus、cmdMultiple、cmdDevide，小数点按钮是cmdDot，负号按钮是cmdMinuse，数字09为了偷懒，用了控件数组cmdNumber(0) cmdNumber(9)，上面txtShow是显示数字和结果用的，txtOperate是显示中间步骤的。思路大致是这样，点加减乘除这类操作符的时候，把当前txtShow的值保存在模块变量mstrParam1里，同时把操作符保存到mstrOperate里，按等于

2、号时把先把当前txtShow的值保存在模块变量mstrParam2里，然后对mstrParam1和mstrParam2进行运算，当然要记得设法把String转换成数值进行运算。 转换的过程要注意，这里是用的Variant数据类型，vParam1和vParam2都是Variant类型，保存的是mstrParam1和mstrParam2的数值。之所以不用integer、long、double这些标准类型，是因为这些类型都有大小限制，做出来用着不方便，VB最大的整型long才到 2147483647，这意味着计算器的计算结果只能限制在9位到10位。而Variant类型可以支持非常大的数，具体多大不清

3、楚，但起码几十位是能够支持的。另外，最后算完的结果也要做格式化，因为如果数值非常大的话，VB会自动转成科学计数法，所以要用Format函数进行调整。如果需要源代码的话在我百度空间里留言。Option ExplicitPrivate Const mstrFORMATDEFAULT As String = "#.#"Private mstrParam1 As String, mstrParam2 As StringPrivate mstrOperate As StringPrivate Sub cmdAdd_Click() mstrParam1 = Trim(txtShow.T

4、ext) mstrOperate = "+" txtShow.Text = "" txtOperate.Text = txtOperate.Text & mstrParam1 & vbCrLf txtOperate.Text = txtOperate.Text & mstrOperate & vbCrLf End SubPrivate Sub cmdPlus_Click() mstrParam1 = Trim(txtShow.Text) mstrOperate = "-" txtShow.Text =

5、"" txtOperate.Text = txtOperate.Text & mstrParam1 & vbCrLf txtOperate.Text = txtOperate.Text & mstrOperate & vbCrLf End SubPrivate Sub cmdMultiple_Click() mstrParam1 = Trim(txtShow.Text) mstrOperate = "*" txtShow.Text = "" txtOperate.Text = txtOperate.Te

6、xt & mstrParam1 & vbCrLf txtOperate.Text = txtOperate.Text & mstrOperate & vbCrLf End SubPrivate Sub cmdDevide_Click() mstrParam1 = Trim(txtShow.Text) mstrOperate = "/" txtShow.Text = "" txtOperate.Text = txtOperate.Text & mstrParam1 & vbCrLf txtOperate.Te

7、xt = txtOperate.Text & mstrOperate & vbCrLf End SubPrivate Sub cmdDot_Click() Dim mstrShow As String Dim i As Integer mstrShow = "." i = InStr(1, txtShow.Text, mstrShow) If i <= 0 Then txtShow.Text = txtShow.Text & mstrShow End If End SubPrivate Sub cmdMinuse_Click() Dim mst

8、rShow As String Dim i As Integer mstrShow = "-" i = InStr(1, txtShow.Text, mstrShow) If i <= 0 Then txtShow.Text = mstrShow & txtShow.Text Else txtShow.Text = Right(txtShow.Text, Len(txtShow.Text) - 1) End If End SubPrivate Sub cmdNumber_Click(Index As Integer) Dim mstrShow As Strin

9、g mstrShow = Index txtShow.Text = txtShow.Text & mstrShow End SubPrivate Sub cmdClear_Click() txtShow.Text = ""End SubPrivate Sub cmdResult_Click() Dim vParam1 As Variant, vParam2 As Variant Dim vResult As Variant Dim strResult As String Dim i As Long Dim blnBeforeDot As Boolean Dim ln

10、gDotPos As Long Dim blnMinuse As Boolean mstrParam2 = Trim(txtShow.Text) txtOperate.Text = txtOperate.Text & mstrParam2 & vbCrLf vParam1 = 0 blnBeforeDot = True lngDotPos = -1 blnMinuse = False For i = 1 To Len(mstrParam1) If IsNumeric(Mid(mstrParam1, i, 1) = True Then If blnBeforeDot = True

11、 Then vParam1 = vParam1 * 10 + CByte(Mid(mstrParam1, i, 1) Else vParam1 = vParam1 + CByte(Mid(mstrParam1, i, 1) * (0.1 (i - lngDotPos) End If ElseIf Mid(mstrParam1, i, 1) = "." Then blnBeforeDot = False lngDotPos = i ElseIf Mid(mstrParam1, i, 1) = "-" Then blnMinuse = True End If

12、 Next i If blnMinuse = True Then vParam1 = -vParam1 End If vParam2 = 0 blnBeforeDot = True lngDotPos = -1 blnMinuse = False For i = 1 To Len(mstrParam2) If IsNumeric(Mid(mstrParam2, i, 1) = True Then If blnBeforeDot = True Then vParam2 = vParam2 * 10 + CByte(Mid(mstrParam2, i, 1) Else vParam2 = vPar

13、am2 + CByte(Mid(mstrParam2, i, 1) * (0.1 (i - lngDotPos) End If ElseIf Mid(mstrParam2, i, 1) = "." Then blnBeforeDot = False lngDotPos = i ElseIf Mid(mstrParam2, i, 1) = "-" Then blnMinuse = True End If Next i If blnMinuse = True Then vParam2 = -vParam2 End If Select Case mstrOperate Case "+" vResult = vParam1 + vParam2 Case "-" vResult = vParam1 - vParam2 Case "*" vResult = vParam1 * vParam2 Case "/" vResult = vParam1 / vParam2 End Select txtOperate.Text = txtOperate.Text & "=" & vbCrLf strResult =