Attributes

An attribute is a program element that modifies some declaration. Here is a simple example:

<SomeAttribute(  )> Public Class SomeClass
   ' ...
End Class

This example shows a fictitious SomeAttribute attribute that applies to a class declaration. Attributes appear within angle brackets (<>) and are following by parentheses (( )), which may contain a list of arguments. To apply multiple attributes to a single declaration, separate them with commas within a single set of angle brackets, like this:

<SomeAttribute(), SomeOtherAttribute(  )> Public Class SomeClass
   ' ...
End Class

Attributes can be placed on the following kinds of declarations:

Types

This includes classes, delegates, enumerations, events, interfaces, Visual Basic .NET standard modules, and structures.

The attribute is placed at the beginning of the first line of the type declaration:

<SomeAttribute(  )> Public Class SomeClass
   ' ...
End Class
Constructors

The attribute is placed at the beginning of the first line of the constructor declaration:

<SomeAttribute()> Public Sub New(  )
   ' ...
End Sub
Fields

The attribute is placed at the beginning of the field declaration:

<SomeAttribute(  )> Public SomeField As Integer
Methods

The attribute is placed at the beginning of the first line of the method declaration:

<SomeAttribute()> Public Sub SomeMethod(  )
' ...
End Sub
Parameters

The attribute is placed immediately prior to the parameter declaration. Each parameter can have its own attributes:

Public Sub SomeMethod(<SomeAttribute( )> ...

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