Provides functionality to evaluate queries against a specific data source wherein the type of the data is known.
Public Interface IQueryable(Of Out T) _ Inherits IEnumerable(Of T), IQueryable, IEnumerable
Dim instance As IQueryable(Of Out T)
public interface IQueryable<out T> : IEnumerable<T>, IQueryable, IEnumerable
generic<typename T> public interface class IQueryable : IEnumerable<T>, IQueryable, IEnumerable
type IQueryable<'T> = interface interface IEnumerable<'T> interface IQueryable interface IEnumerable end
The type of the data in the data source.
This type parameter is covariant. That is, you can use either the type you specified or any type that is more derived. For more information about covariance and contravariance, see Covariance and Contravariance in Generics.
The IQueryable<(Of <(T>)>) interface is intended for implementation by query providers.
This interface inherits the IEnumerable<(Of <(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<(Of <(T>)>) object to be executed. Queries that do not return enumerable results are executed when the Execute<(Of <(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<(Of <(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<(Of <(T>)>) interface.
For more information about how to create your own LINQ provider, see LINQ: Building an IQueryable Provider on MSDN Blogs.
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008, Windows Server 2003