AddressOf. This VB.NET operator enables delegate functions. With it we reference a method and use it as the implementation for a delegate.
Operator syntax. We use the name of a function and specify it where a delegate is required. We can use AddressOf to reference a function instead of a lambda.
Example. This program introduces the IsThreeLetters Function, which receives a String and returns a Boolean. This Function is used as a delegate. In Main we create a List and add 3 values to it.
Then The List.Find Function is used to find the first 3-letter String in the List instance.
Module Module1
Function IsThreeLetters(ByVal value As String) As Boolean
Return value.Length = 3
End Function
Sub Main()
Dim list As List(Of String) = New List(Of String)
list.Add("mouse")
list.Add("horse")
list.Add("dog")
Dim value As String = list.Find(AddressOf IsThreeLetters)
Console.WriteLine(value)
End Sub
End Moduledog
Discussion. In the C# language, you do not need AddressOf. Instead, you can use the method name directly as the delegate. The AddressOf operator may be less confusing.
Info AddressOf introduces the context in which the method name should be referenced. The method name is just used to acquire a memory address.
Summary. The AddressOf operator references an existing Function and turns it into a delegate. We do not need to use lambda expression syntax. We can use existing functions.
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Sam Allen is passionate about computer languages. In the past, his work has been recommended by Apple and Microsoft and he has studied computers at a selective university in the United States.
This page was last updated on Mar 20, 2022 (rewrite).