GroupBy<TKey,TElement,TResult>(Expression<Func<T,TKey>>,Expression<Func<T,TElement>>,Expression<Func<TKey,IEnumerable<TElement>,TResult>>) Method

Groups the elements of a view according to a specified key selector function and creates a result value from each group and its key. The elements of each group are projected by using a specified function.

Syntax

Visual Basic
C#

'Declaration
 
Public Overloads Function GroupBy
    (Of TKey,TElement,TResult)( _
   ByVal keySelector As System.Linq.Expressions.Expression(Of Func(Of T,TKey)), _
   ByVal elementSelector As System.Linq.Expressions.Expression(Of Func(Of T,TElement)), _
   ByVal resultSelector As System.Linq.Expressions.Expression(Of Func(Of TKey,IEnumerable(Of TElement),TResult)) _
) As View(Of TResult)

public View<TResult> GroupBy<TKey,TElement,TResult>( 
   System.Linq.Expressions.Expression<Func<T,TKey>> keySelector,
   System.Linq.Expressions.Expression<Func<T,TElement>> elementSelector,
   System.Linq.Expressions.Expression<Func<TKey,IEnumerable<TElement>,TResult>> resultSelector
)

Parameters

keySelector: A function to extract the key for each element.
elementSelector: A function to map each source element to an element in the System.Linq.IGrouping`2.
resultSelector: A function to create a result value from each group.

Type Parameters

TKey: The type of the key returned by keySelector.
TElement: The type of the elements in groups.
TResult: The type of the result value returned by resultSelector.

Return Value

A view of elements of type TResult where each element represents a projection over a group and its key.

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

View<T> Class
View<T> Members
Overload List