利用API 实现字符串表达式的计算

最新推荐文章于 2024-07-05 18:43:03 发布

最新推荐文章于 2024-07-05 18:43:03 发布 · 102 阅读

此博客展示了一段字符串表达式计算代码，该代码由论坛代码改编。代码包含函数声明、执行代码行的函数、计算函数等，可实现对字符串表达式的计算，并将结果通过消息框显示，如示例表达式“1+2*3 - 4/5”。

下面实现字符串表达式计算代码由笔者收藏的本论坛代码改编，记不清是哪位网友提供的了，非常感谢。

Option Explicit
Private Declare Function EbExecuteLine Lib "vba6.dll" (ByVal pStringToExec As Long, ByVal Unknownn1 As Long, ByVal Unknownn2 As Long, ByVal fCheckOnly As Long) As Long

Private Function ExecuteLine(sCode As String, Optional fCheckOnly As Boolean) As Boolean
ExecuteLine = EbExecuteLine(StrPtr(sCode), 0&, 0&, Abs(fCheckOnly)) = 0
End Function

Sub calc(ByVal x As String)
Dim result
ExecuteLine "dim x as double"
ExecuteLine "x= " & x
ExecuteLine "clipboard.settext x"
result = Clipboard.GetText
MsgBox x & "=" & result
Set result = Nothing
End Sub

Private Sub Command1_Click()
calc Text1
End Sub

Private Sub Form_Load()
Text1.Text = "1+2*3-4/5"
End Sub