Queryable::Any<TSource> Method (IQueryable<TSource>)
Determines whether a sequence contains any elements.
Assembly: System.Core (in System.Core.dll)
[ExtensionAttribute] public: generic<typename TSource> static bool Any( IQueryable<TSource>^ source )
Type Parameters
- TSource
The type of the elements of source.
Parameters
- source
- Type: System.Linq::IQueryable<TSource>
A sequence to check for being empty.
Return Value
Type: System::Booleantrue if the source sequence contains any elements; otherwise, false.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type IQueryable<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).| Exception | Condition |
|---|---|
| ArgumentNullException | source is nullptr. |
The Any<TSource>(IQueryable<TSource>) method generates a MethodCallExpression that represents calling Any<TSource>(IQueryable<TSource>) itself as a constructed generic method. It then passes the MethodCallExpression to the Execute<TResult>(Expression) method of the IQueryProvider represented by the Provider property of the source parameter.
The query behavior that occurs as a result of executing an expression tree that represents calling Any<TSource>(IQueryable<TSource>) depends on the implementation of the type of the source parameter. The expected behavior is that it determines if source contains any elements.
The following code example demonstrates how to use Any<TSource>(IQueryable<TSource>) to determine whether a sequence contains any elements.
The Boolean value that the Any<TSource>(IQueryable<TSource>) method returns is typically used in the predicate of a where clause (Where clause in Visual Basic) or a direct call to the Where<TSource>(IQueryable<TSource>, Expression<Func<TSource, Boolean>>) method. The following example demonstrates this use of the Any method.
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003
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.