Jas*_*son 7 .net vb.net parameters properties function
我正在尝试创建一个函数,当一个属性作为参数传递给它时,它返回用于将属性定义为字符串的名称.例如,
Shared Function PropertyToStr(Propert As Object)
'Code to get property name and return it as a string goes here
End Function
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提供这First_Name是属性的名称,定义如下:
Property First_Name as String
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该功能应该像:
Dim str as String = PropertyToStr(First_Name) ' Resulting in str = "First_Name"
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注意我只想在此函数中返回属性名称"First_Name",而不是"MyClass.First_Name".
我找到了我的函数类似代码的其他示例,我需要用c#编写,但我无法复制他们在VB.Net中使用MemberExpression
Joh*_*ner 11
编辑:在Visual Studio 2015中,您可以使用NameOf运算符来完成此操作:
Property First_Name As String
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
MessageBox.Show(NameOf(First_Name))
End Sub
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旧版.net的原始答案:
通过一些代码转换器运行其他答案并清理它会产生以下结果,这似乎工作得很好.
Private Shared Function GetMemberInfo(method As Expression) As MemberExpression
Dim lambda As LambdaExpression = TryCast(method, LambdaExpression)
If lambda Is Nothing Then
Throw New ArgumentNullException("method")
End If
Dim memberExpr As MemberExpression = Nothing
If lambda.Body.NodeType = ExpressionType.Convert Then
memberExpr = TryCast(DirectCast(lambda.Body, UnaryExpression).Operand, MemberExpression)
ElseIf lambda.Body.NodeType = ExpressionType.MemberAccess Then
memberExpr = TryCast(lambda.Body, MemberExpression)
End If
If memberExpr Is Nothing Then
Throw New ArgumentException("method")
End If
Return memberExpr
End Function
Public Shared Function GetPropertyName(Of T)(prop As Expression(Of Func(Of T))) As String
Dim expression = GetMemberInfo(prop)
Return expression.Member.Name
End Function
Property First_Name As String
Property LastName As String
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
MessageBox.Show(GetPropertyName(Function() First_Name))
MessageBox.Show(GetPropertyName(Function() LastName))
End Sub
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