Enumerable..::.Any<(Of <(TSource>)>) Method (IEnumerable<(Of <(TSource>)>), Func<(Of <(TSource, Boolean>)>))
This page is specific to:.NET Framework Version:3.5Silverlight 34.0
.NET Framework Class Library
Enumerable..::.Any<(Of <(TSource>)>) Method (IEnumerable<(Of <(TSource>)>), Func<(Of <(TSource, Boolean>)>))

Determines whether any element of a sequence satisfies a condition.

Namespace:  System.Linq
Assembly:  System.Core (in System.Core.dll)
Syntax

'Usage

Dim source As IEnumerable(Of TSource)
Dim predicate As Func(Of TSource, Boolean)
Dim returnValue As Boolean

returnValue = source.Any(predicate)

'Declaration

<ExtensionAttribute> _
Public Shared Function Any(Of TSource) ( _
    source As IEnumerable(Of TSource), _
    predicate As Func(Of TSource, Boolean) _
) As Boolean

Type Parameters

TSource

The type of the elements of source.

Parameters

source
Type: System.Collections.Generic..::.IEnumerable<(Of <(TSource>)>)
An IEnumerable<(Of <(T>)>) whose elements to apply the predicate to.
predicate
Type: System..::.Func<(Of <(TSource, Boolean>)>)
A function to test each element for a condition.

Return Value

Type: System..::.Boolean
true if any elements in the source sequence pass the test in the specified predicate; otherwise, false.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IEnumerable<(Of <(TSource>)>). When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).
Exceptions

ExceptionCondition
ArgumentNullException

source or predicate is nullNothingnullptra null reference (Nothing in Visual Basic).

Remarks

NoteNote:

This method does not return any one element of a collection. Instead, it determines whether any elements of a collection satisfy a condition.

The enumeration of source is stopped as soon as the result can be determined.

In Visual Basic query expression syntax, an Aggregate Into Any() clause translates to an invocation of Any.

Examples

The following code example demonstrates how to use Any to determine whether any element in a sequence satisfies a condition.

Structure Pet
    Public Name As String
    Public Age As Integer
    Public Vaccinated As Boolean
End Structure

Shared Sub AnyEx3()
    ' Create a list of Pets
    Dim pets As New List(Of Pet)(New Pet() _
                                 {New Pet With {.Name = "Barley", .Age = 8, .Vaccinated = True}, _
                                  New Pet With {.Name = "Boots", .Age = 4, .Vaccinated = False}, _
                                  New Pet With {.Name = "Whiskers", .Age = 1, .Vaccinated = False}})

    ' Determine whether any pets over age 1 are also unvaccinated.
    Dim unvaccinated As Boolean = _
        pets.Any(Function(pet) pet.Age > 1 And pet.Vaccinated = False)

    ' Display the output.
    Dim text As String = IIf(unvaccinated, "are", "are not")
    MsgBox("There " & text & " unvaccinated animals over age 1.")
End Sub

' This code produces the following output:
'
' There are unvaccinated animals over age 1.



Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Version Information

.NET Framework

Supported in: 3.5

.NET Compact Framework

Supported in: 3.5

XNA Framework

Supported in: 3.0
See Also

Reference

Other Resources

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