EFDataSource.BeforeLoadCustomAssembly Event

Occurs on an attempt to load a custom assembly by EFDataSource.

Namespace: DevExpress.DataAccess.EntityFramework

Assembly: DevExpress.DataAccess.v19.2.dll


public event BeforeLoadCustomAssemblyEventHandler BeforeLoadCustomAssembly
Public Event BeforeLoadCustomAssembly As BeforeLoadCustomAssemblyEventHandler

Event Data

The BeforeLoadCustomAssembly event handler receives an argument of the BeforeLoadCustomAssemblyEventArgs type. The following properties provide information specific to this event.

Property Description
AllowLoading Specifies whether loading a custom assembly is allowed.
AssemblyPath Specifies the path to a requested assembly.
ContextName Specifies the type to load from a custom assembly.


Loading of custom assemblies that may be referenced by Entity Framework data sources is forbidden by default.

To permit loading a specific assembly, handle the BeforeLoadCustomAssembly event (or static EFDataSource.BeforeLoadCustomAssemblyGlobal event) and specify the following properties of the BeforeLoadCustomAssemblyEventArgs object.

An unauthorized attempt to load a custom assembly will result in throwing a CustomAssemblyLoadingProhibitedException.

In the Data Source wizard, the corresponding option is disabled so that end-users are only allowed to select a data context from assemblies referenced by the project.


To make the Browse button visible, set the EFWizardSettings.ShowBrowseButton property to true.


See Also