FirstOrNullEntity<TEntity>(IEntityQuery<TEntity>,Expression<Func<TEntity,Boolean>>) Method

Returns the first element of a sequence, or the appropriate NullEntity if no element is found.

Syntax

Visual Basic
C#

'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Function FirstOrNullEntity(Of TEntity As Class)( _
   ByVal source1 As IEntityQuery(Of TEntity), _
   ByVal predicate As Expression(Of Func(Of TEntity,Boolean)) _
) As TEntity

'Usage
 
Dim source1 As IEntityQuery(Of TEntity)
Dim predicate As Expression(Of Func(Of TEntity,Boolean))
Dim value As TEntity
 
value = EntityQueryExtensions.FirstOrNullEntity(Of TEntity)(source1, predicate)

[Extension()]
public static TEntity FirstOrNullEntity<TEntity>( 
   IEntityQuery<TEntity> source1,
   Expression<Func<TEntity,bool>> predicate
)
where TEntity: class

Parameters

source1
predicate

Type Parameters

TEntity

Example

var mgr1 = new DomainModelEntityManager();
Customer cust = mgr1.Customers.FirstOrNullEntity(c => c.Country == "UK");

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

EntityQueryExtensions Class
EntityQueryExtensions Members
Overload List