form1.frm

用Excel计算代数式,代码简单易懂

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Form1"
   ClientHeight    =   3195
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3195
   ScaleWidth      =   4680
   StartUpPosition =   3  '窗口缺省
   Begin VB.TextBox Text1 
      Height          =   585
      Left            =   555
      TabIndex        =   1
      Text            =   "Text1"
      Top             =   270
      Width           =   2205
   End
   Begin VB.CommandButton Command1 
      Caption         =   "Command1"
      Height          =   1035
      Left            =   1545
      TabIndex        =   0
      Top             =   1080
      Width           =   1890
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit

Function result(ByVal x As String) As String
    Dim myobj As Object
    Set myobj = CreateObject("excel.sheet")
    Set myobj = myobj.Application.ActiveWorkbook.ActiveSheet
    myobj.Range("a1").Formula = "= " & x '
    result = CStr(myobj.Range("a1").Value)
    Set myobj = Nothing

End Function

Private Sub Command1_Click()
    Dim x As String
    x = Text1.Text
    MsgBox x & "=" & result(x)
End Sub

Private Sub Form_Load()
    Text1.Text = "3*9+435-34*34.56" '错误表达式，返回错误信息。你可以改成合法表达式再按单击COMMAND1
End Sub