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EnumerableRowCollectionExtensions.Select<TRow,S> Method

Definition

Projects each element of an EnumerableRowCollection<TRow> into a new form.

This API supports the product infrastructure and is not intended to be used directly from your code.

public:
generic <typename TRow, typename S>
[System::Runtime::CompilerServices::Extension]
 static System::Data::EnumerableRowCollection<S> ^ Select(System::Data::EnumerableRowCollection<TRow> ^ source, Func<TRow, S> ^ selector);
public static System.Data.EnumerableRowCollection<S> Select<TRow,S> (this System.Data.EnumerableRowCollection<TRow> source, Func<TRow,S> selector);
static member Select : System.Data.EnumerableRowCollection<'Row> * Func<'Row, 'S> -> System.Data.EnumerableRowCollection<'S>
<Extension()>
Public Function Select(Of TRow, S) (source As EnumerableRowCollection(Of TRow), selector As Func(Of TRow, S)) As EnumerableRowCollection(Of S)

Type Parameters

TRow

The type of the row elements in source, typically DataRow.

S

The type that TRow will be transformed into.

Parameters

source
EnumerableRowCollection<TRow>

An EnumerableRowCollection<TRow> containing the DataRow elements to invoke a transform function upon.

selector
Func<TRow,S>

A transform function to apply to each element.

Returns

An EnumerableRowCollection<TRow> whose elements are the result of invoking the transform function on each element of source.

Remarks

This method is implemented by using deferred execution. The immediate return value is an object that stores all the information that is required to perform the action. The query represented by this method is not executed until the object is enumerated either by calling its GetEnumerator method directly or by using foreach in Visual C# or For Each in Visual Basic.

This projection method requires the transform function, selector, to produce one value for each value in the source sequence, source. If selector returns a value that is itself a collection, it is up to the consumer to traverse the subsequences manually.

Applies to