Question

我在Access数据库中有这个类模块：

Option Compare Database

Public Event BeforeCalc()

Public Sub Calculate(ByVal i As Integer, ByVal y As Integer)
    RaiseEvent BeforeCalc
    Calculate = i + y
End Sub


Private Sub Class_Initialize()
    Debug.Print "Inside construcotr"
End Sub

然后，在自定义表单中：

Option Compare Database

Private WithEvents math As MyMath

Private Sub btnCalculate_Click()
    Dim result As Integer
    Set result = math.Calculate(CInt(txtI.Text), CInt(txtY.Text))
End Sub

Private Sub Form_Load()
    Set math = New MyMath
End Sub

Private Sub math_BeforeCalc()
    MsgBox "About to Calc!", vbInformation
End Sub

当我点击表格按钮btnCalculate时，我在math.Calculate收到了这个错误：

“编译错误。预期的功能或变量。”

我的代码出了什么问题？

Answer 1

因为它是一个函数所以它应该返回一些东西，在你的情况下是一个整数，你也应该指定Function关键字。

替换代码：

Public Sub Calculate(ByVal i As Integer, ByVal y As Integer)
     RaiseEvent BeforeCalc
     Calculate = i + y
End Sub

with：

Public Function Calculate(ByVal i As Integer, ByVal y As Integer) as Integer
    RaiseEvent BeforeCalc
    Calculate = i + y
End Sub

Answer 2

您已将Calculate定义为Sub，尝试将其定义为Function：

Public Function Calculate(ByVal i As Integer, ByVal y As Integer) as Integer
    RaiseEvent BeforeCalc
    Calculate = i + y
End Function

另外，不要set结果：

Private Sub btnCalculate_Click()
    Dim result As Integer
    result = math.Calculate(CInt(txtI.Text), CInt(txtY.Text))
End Sub

在VBA中调用类函数时出错

2 个答案: