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DbExpressionBuilder.OfType(DbExpression, TypeUsage) Method

Definition

Creates a new DbOfTypeExpression that produces a set consisting of the elements of the given input set that are of the specified type.

public:
[System::Runtime::CompilerServices::Extension]
 static System::Data::Common::CommandTrees::DbOfTypeExpression ^ OfType(System::Data::Common::CommandTrees::DbExpression ^ argument, System::Data::Metadata::Edm::TypeUsage ^ type);
public static System.Data.Common.CommandTrees.DbOfTypeExpression OfType (this System.Data.Common.CommandTrees.DbExpression argument, System.Data.Metadata.Edm.TypeUsage type);
static member OfType : System.Data.Common.CommandTrees.DbExpression * System.Data.Metadata.Edm.TypeUsage -> System.Data.Common.CommandTrees.DbOfTypeExpression
<Extension()>
Public Function OfType (argument As DbExpression, type As TypeUsage) As DbOfTypeExpression

Parameters

argument
DbExpression

A DbExpression that specifies the input set.

type
TypeUsage

Type metadata for the type that elements of the input set must have to be included in the resulting set.

Returns

A new DbOfTypeExpression with the specified set argument and type, and an ExpressionKind of OfType.

Exceptions

argument or type is null.

argument does not have a collection result type, or type is not a type in the same type hierarchy as the element type of the collection result type of argument.

Remarks

DbOfTypeExpression requires that argument has a collection result type with a polymorphic element type, and that type is a type from the same type hierarchy as that element type.

Applies to