使用CallByName访问子类或子属性

时间:2013-03-24 19:33:47

标签: vb.net callbyname

我可以使用 CallByName 访问班次'子值(换句话说,我可以使用Class.SubValue)。
但是当我想使用CallByName获取Class.SUBCLASS.SubValue时,我会收到错误 是否可以使用CallByName(或使用smtg else)?

这是一个典型的代码:

Class Class1
    Public someVariable as Long=123 'now "Class1" has "someVariable" 
End Class
Class Class2
    Public subClass as new Class1   'now "Class2" has a SUBCLASS "Class1" 
End Class

Sub Test()
    Dim c1 as New Class1, c2 as New Class2
        'This works fine, and I can get c1.someVariable. It's OK.
    a=CallByName(c1,"someVariable",CallType.Get)
        'But I get error here... and I can't get c2.subClass.someVariable
    b=CallByName(c2,"subClass.someVariable",CallType.Get)
End Sub

- 编辑:这是实际问题。 -

我想从文件中加载参数以形成控件,在文件中参数的写法如下:
<ControlName>.<Property>=<Value> | TextBox1.Text=SomeText | Button2.Left=1234
我使用时出错:
CallByName(MyForm, "<ControlName>.<Property>", CallType.Set, "<Value>")

如何解决我的问题(使用CallByName或smtg else)?

2 个答案:

答案 0 :(得分:2)

我使用了这个简单的递归函数

  Function RecursiveGetValue(ByVal Name As String, ByVal Data As Object) As Object
If Name.Contains(".") = True Then
  RecursiveGetValue = RecursiveGetValue(Name.Substring(Name.IndexOf(".") + 1), CallByName(Data, Name.Split(".")(0), CallType.Get))
Else
  RecursiveGetValue = CallByName(Data, Name, CallType.Get)
End If

结束功能

答案 1 :(得分:0)

我正在做类似的事情。我希望能够在SQL列名称中使用点符号来递归地填充对象层次结构。

Sub PopulateData(r As SqlDataReader)
    For i As Integer = 0 To r.FieldCount - 1
        If Len(r(i)) > 0 Then
            Try
                Dim ob As Object = Me
                Dim name As String = r.GetName(i)

                While InStr(name, ".") > 0
                    ob = CallByName(ob, Split(name, ".")(0), CallType.Get)
                    name = name.Substring(InStr(name, "."))
                End While

                CallByName(ob, name, CallType.Set, r(i))


            Catch ex As Exception
                Console.WriteLine("Missing property: {0}", r.GetName(i))

            End Try

        End If

    Next

End Sub