System.Linq Namespace ()

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Microsoft Visual Studio 2008/.NET Framework 3.5

Other versions are also available for the following:

.NET Framework Class Library

System.Linq Namespace

The System.Linq namespace provides classes and interfaces that support queries that use Language-Integrated Query (LINQ).

The Enumerable class contains LINQ standard query operators that operate on objects that implement IEnumerable<(Of <(T>)>).

The Queryable class contains LINQ standard query operators that operate on objects that implement IQueryable<(Of <(T>)>).

Classes

	Class	Description
	Enumerable	Provides a set of static (Shared in Visual Basic) methods for querying objects that implement IEnumerable<(Of <(T>)>).
	Lookup<(Of <(TKey, TElement>)>)	Represents a collection of keys each mapped to one or more values.
	Queryable	Provides a set of static (Shared in Visual Basic) methods for querying data structures that implement IQueryable<(Of <(T>)>).

Interfaces

	Interface	Description
	IGrouping<(Of <(TKey, TElement>)>)	Represents a collection of objects that have a common key.
	ILookup<(Of <(TKey, TElement>)>)	Defines an indexer, size property, and Boolean search method for data structures that map keys to IEnumerable<(Of <(T>)>) sequences of values.
	IOrderedEnumerable<(Of <(TElement>)>)	Represents a sorted sequence.
	IOrderedQueryable	Represents the result of a sorting operation.
	IOrderedQueryable<(Of <(T>)>)	Represents the result of a sorting operation.
	IQueryable	Provides functionality to evaluate queries against a specific data source wherein the type of the data is not specified.
	IQueryable<(Of <(T>)>)	Provides functionality to evaluate queries against a specific data source wherein the type of the data is known.
	IQueryProvider	Defines methods to create and execute queries that are described by an IQueryable object.