Returns whether the current instance is a null entity.
Syntax
Visual Basic (Declaration) | |
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Public ReadOnly Property IsNullEntity As Boolean |
Visual Basic (Usage) | Copy Code |
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Dim instance As EntityAspect
Dim value As Boolean
value = instance.IsNullEntity |
C# | |
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public bool IsNullEntity {get;} |
C++/CLI | |
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public:
property bool IsNullEntity {
bool get();
} |
Example
C# | Copy Code |
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// Sample showing IsNullEntity check.
DomainModelEntityManager mgr = new DomainModelEntityManager();
// Try to retrieve order #1 - FirstOrNullEntity will return null entity if not found.
OrderSummary order = mgr.OrderSummaries.FirstOrNullEntity(o => o.Id == 1);
if (order.IsNullEntity)
Console.WriteLine("Order #1 not found");
// Now try another order, using FirstOrDefault, which returns null if not found.
OrderSummary order2 = mgr.OrderSummaries.FirstOrDefault(o => o.Id == 2);
if (order2 == null) {
Console.WriteLine("Order #2 is null");
} else if (order2.IsNullEntity) {
Console.WriteLine("Order #2 is a null entity");
}
// Note, you can't use .First (since the EF will throw an exception).
OrderSummary order3 = mgr.OrderSummaries.First(o => o.Id == 3); |
Remarks
Requirements
Target Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows Server 2008 family
See Also