的小程序計算器

1、VB6.0的小程序 計算器對于剛?cè)腴T學習VB6的朋友來說肯定會做些小程序吧，這里就是給大家演示個簡單的計算器程序，僅供參考啦。界面上加減乘除四個按鈕分別是cmdAdd、cmdPlus、cmdMultiple、cmdDevide，小數(shù)點按鈕是cmdDot，負號按鈕是cmdMinuse，數(shù)字09為了偷懶，用了控件數(shù)組cmdNumber(0) cmdNumber(9)，上面txtShow是顯示數(shù)字和結(jié)果用的，txtOperate是顯示中間步驟的。思路大致是這樣，點加減乘除這類操作符的時候，把當前txtShow的值保存在模塊變量mstrParam1里，同時把操作符保存到mstrOperate里，按等于

2、號時把先把當前txtShow的值保存在模塊變量mstrParam2里，然后對mstrParam1和mstrParam2進行運算，當然要記得設法把String轉(zhuǎn)換成數(shù)值進行運算。 轉(zhuǎn)換的過程要注意，這里是用的Variant數(shù)據(jù)類型，vParam1和vParam2都是Variant類型，保存的是mstrParam1和mstrParam2的數(shù)值。之所以不用integer、long、double這些標準類型，是因為這些類型都有大小限制，做出來用著不方便，VB最大的整型long才到 2147483647，這意味著計算器的計算結(jié)果只能限制在9位到10位。而Variant類型可以支持非常大的數(shù)，具體多大不清

3、楚，但起碼幾十位是能夠支持的。另外，最后算完的結(jié)果也要做格式化，因為如果數(shù)值非常大的話，VB會自動轉(zhuǎn)成科學計數(shù)法，所以要用Format函數(shù)進行調(diào)整。如果需要源代碼的話在我百度空間里留言。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 =