Queryable::Contains<TSource> Method (IQueryable<TSource>, TSource)
Determines whether a sequence contains a specified element by using the default equality comparer.
Namespace: System.Linq
Assembly: System.Core (in System.Core.dll)
Type Parameters
- TSource
The type of the elements of source.
Parameters
- source
- Type: System.Linq::IQueryable<TSource>
An IQueryable<T> in which to locate item.
- item
- Type: TSource
The object to locate in the sequence.
Return Value
Type: System::Booleantrue if the input sequence contains an element that has the specified value; 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.| Exception | Condition |
|---|---|
| ArgumentNullException | source is nullptr. |
The Contains<TSource>(IQueryable<TSource>, TSource) method generates a MethodCallExpression that represents calling Contains<TSource>(IQueryable<TSource>, 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 Contains<TSource>(IQueryable<TSource>, TSource) depends on the implementation of the type of the source parameter. The expected behavior is that it determines if source contains item.
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.