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System.Linq Namespace

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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<T>.

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

Classes

  Class Description
Public class Enumerable Provides a set of static (Shared in Visual Basic) methods for querying objects that implement IEnumerable<T>.
Public class EnumerableExecutor Represents an expression tree and provides functionality to execute the expression tree after rewriting it.
Public class EnumerableExecutor<T> Infrastructure. Represents an expression tree and provides functionality to execute the expression tree after rewriting it.
Public class EnumerableQuery Infrastructure. Represents an IEnumerable as an EnumerableQuery data source.
Public class EnumerableQuery<T> Infrastructure. Represents an IEnumerable<T> collection as an IQueryable<T> data source.
Public class Lookup<TKey, TElement> Represents a collection of keys each mapped to one or more values.
Public class Queryable Provides a set of static (Shared in Visual Basic) methods for querying data structures that implement IQueryable<T>.

Interfaces

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