EFDataSource.BeforeLoadCustomAssemblyGlobal Event

Occurs on an attempt to load a custom assembly by EFDataSource (e.g., when an application loads a report template containing an Entity Framework data source originated from a compiled assembly).

Namespace: DevExpress.DataAccess.EntityFramework

Assembly: DevExpress.DataAccess.v21.2.dll


public static event BeforeLoadCustomAssemblyEventHandler BeforeLoadCustomAssemblyGlobal

Event Data

The BeforeLoadCustomAssemblyGlobal event's data class is BeforeLoadCustomAssemblyEventArgs. 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 EFDataSource.BeforeLoadCustomAssembly event (or static 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.


The following code snippets (auto-collected from DevExpress Examples) contain references to the BeforeLoadCustomAssemblyGlobal event.


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See Also