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ObjectContext.LoadProperty(TEntity) Method (TEntity, Expression(Func(TEntity, Object)), MergeOption)

Explicitly loads an object that is related to the supplied object by the specified LINQ query and by using the specified merge option.

Namespace:  System.Data.Objects
Assembly:  System.Data.Entity (in System.Data.Entity.dll)

member LoadProperty : 
        entity:'TEntity * 
        selector:Expression<Func<'TEntity, Object>> * 
        mergeOption:MergeOption -> unit

Type Parameters

TEntity

Parameters

entity
Type: TEntity

The source object for which related objects are to be loaded.

selector
Type: System.Linq.Expressions.Expression(Func(TEntity, Object))

A LINQ expression that defines the related objects to be loaded.

mergeOption
Type: System.Data.Objects.MergeOption

The MergeOption value to use when you load the related objects.

ExceptionCondition
ArgumentException

selector does not supply a valid input parameter.

ArgumentNullException

selector is null.

InvalidOperationException

The entity is in a Detached, [F:System.Data.EntityState.Added,] or Deleted state,

-or-

The entity is attached to another instance of ObjectContext.

The LoadProperty method must be called to achieve explicit loading when you are using POCO custom data classes.

After calling LoadProperty, the related object can be accessed through the navigation properties of the source entity.

The property to load is specified by a LINQ expression, which must be in the form of a simple property member access, as in (entity) => entity.PropertyName where PropertyName is the navigation property that returns the related objects to be loaded. An exception will occur if other forms of the LINQ expression are used.

When using POCO custom data classes, related objects cannot be explicitly loaded like instances of entity types that are generated by the Entity Data Model tools. This is because the tools generate the navigation properties that return an EntityCollection(TEntity) or EntityReference(TEntity) of related objects when Load is called on a RelatedEnd. POCO entities can still be loaded by using lazy loading by setting the LazyLoadingEnabled property to true on the instance of ObjectContextOptions that is returned by the ObjectContext.ContextOptions property, or by using eager loading with the Include method on the ObjectQuery(T).

.NET Framework

Supported in: 4.5, 4

.NET Framework Client Profile

Supported in: 4

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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