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NameOf operator - Visual Basic

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The NameOf operator obtains the name of a variable, type, or member as the string constant:

Console.WriteLine(NameOf(System.Collections.Generic))  ' output: Generic
Console.WriteLine(NameOf(List(Of Integer)))  ' output: List
Console.WriteLine(NameOf(List(Of Integer).Count))  ' output: Count
Console.WriteLine(NameOf(List(Of Integer).Add))  ' output: Add

Dim numbers As New List(Of Integer) From { 1, 2, 3 }
Console.WriteLine(NameOf(numbers))  ' output: numbers
Console.WriteLine(NameOf(numbers.Count))  ' output: Count
Console.WriteLine(NameOf(numbers.Add))  ' output: Add

As the preceding example shows, in the case of a type and a namespace, the produced name is usually not fully qualified.

The NameOf operator is evaluated at compile time, and has no effect at run time.

You can use the NameOf operator to make the argument-checking code more maintainable:

Private _name As String

Public Property Name As String
    Get
        Return _name
    End Get
    Set
        If value Is Nothing Then
            Throw New ArgumentNullException(NameOf(value), $"{NameOf(name)} cannot be null.")
        End If
    End Set
End Property

The NameOf operator is available in Visual Basic 14 and later.

See also