IQueryable<T> IQueryable<T> IQueryable<T> IQueryable<T> Interface


Provides functionality to evaluate queries against a specific data source wherein the type of the data is known.

generic <typename T>
public interface class IQueryable : System::Collections::Generic::IEnumerable<T>, System::Linq::IQueryable
public interface IQueryable<out T> : System.Collections.Generic.IEnumerable<out T>, System.Linq.IQueryable
type IQueryable<'T> = interface
    interface seq<'T>
    interface IQueryable
    interface IEnumerable
Public Interface IQueryable(Of Out T)
Implements IEnumerable(Of Out T), IQueryable

Type Parameters


The type of the data in the data source.



The IQueryable<T> interface is intended for implementation by query providers.

This interface inherits the IEnumerable<T> interface so that if it represents a query, the results of that query can be enumerated. Enumeration forces the expression tree associated with an IQueryable<T> object to be executed. Queries that do not return enumerable results are executed when the Execute<TResult>(Expression) method is called.

The definition of "executing an expression tree" is specific to a query provider. For example, it may involve translating the expression tree to a query language appropriate for an underlying data source.

The IQueryable<T> interface enables queries to be polymorphic. That is, because a query against an IQueryable data source is represented as an expression tree, it can be executed against different types of data sources.

The static (Shared in Visual Basic) methods defined in the class Queryable (except for AsQueryable, ThenBy, and ThenByDescending) extend objects of types that implement the IQueryable<T> interface.

For more information about how to create your own LINQ provider, see LINQ: Building an IQueryable Provider on MSDN Blogs.


GetEnumerator() GetEnumerator() GetEnumerator() GetEnumerator()

Returns an enumerator that iterates through a collection.

(Inherited from IEnumerable)


ElementType ElementType ElementType ElementType

Gets the type of the element(s) that are returned when the expression tree associated with this instance of IQueryable is executed.

(Inherited from IQueryable)

Expression Expression Expression Expression

Gets the expression tree that is associated with the instance of IQueryable.

(Inherited from IQueryable)

Provider Provider Provider Provider

Gets the query provider that is associated with this data source.

(Inherited from IQueryable)

Applies to

See also