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Enumerable::FirstOrDefault<TSource> Method (IEnumerable<TSource>^, Func<TSource, Boolean>^)

 

Returns the first element of the sequence that satisfies a condition or a default value if no such element is found.

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

public:
generic<typename TSource>
[ExtensionAttribute]
static TSource FirstOrDefault(
	IEnumerable<TSource>^ source,
	Func<TSource, bool>^ predicate
)

Parameters

source
Type: System.Collections.Generic::IEnumerable<TSource>^

An IEnumerable<T> to return an element from.

predicate
Type: System::Func<TSource, Boolean>^

A function to test each element for a condition.

Return Value

Type: TSource

default(TSource) if source is empty or if no element passes the test specified by predicate; otherwise, the first element in source that passes the test specified by predicate.

Type Parameters

TSource

The type of the elements of source.

Exception Condition
ArgumentNullException

source or predicate is null.

The default value for reference and nullable types is null.

The following code example demonstrates how to use FirstOrDefault<TSource>(IEnumerable<TSource>^, Func<TSource, Boolean>^) by passing in a predicate. In the second call to the method, there is no element in the array that satisfies the condition.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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