' Visual Basic .NET Document
Option Strict On

' <Snippet18>
<Assembly: CLSCompliant(True)>

<AttributeUsageAttribute(AttributeTargets.Class Or AttributeTargets.Struct)> _
Public Class NumericAttribute
    Private _isNumeric As Boolean

    Public Sub New(isNumeric As Boolean)
        _isNumeric = isNumeric
    End Sub

    Public ReadOnly Property IsNumeric As Boolean
        Get
            Return _isNumeric
        End Get
    End Property
End Class

<Numeric(True)> Public Structure UDouble
    Dim Value As Double
End Structure
' Compilation produces a compiler error like the following:
'    error BC31504: 'NumericAttribute' cannot be used as an attribute because it 
'    does not inherit from 'System.Attribute'.
'    
'    <Numeric(True)> Public Structure UDouble
'     ~~~~~~~~~~~~~
' </Snippet18>

Module Example
    Public Sub Main()

    End Sub
End Module