IExpressionEditorService Interface

Definition

Namespace:

System.Activities.Presentation.View

Assembly:

System.Activities.Presentation.dll

Creates or closes expression editors.

public interface class IExpressionEditorService

public interface IExpressionEditorService

type IExpressionEditorService = interface

Public Interface IExpressionEditorService

Remarks

An expression editor is a Visual Basic control used to edit expressions inside Visual Studio. This control provides a full-fledged IDE editing experience, including IntelliSense, colorization, ParamInfo, error squiggles, among other features.

The IExpressionEditorService can also be used to manage instances of custom expression editors. To register a custom expression editor, you must publish the IExpressionEditorService using the following code :

this.expressionEditorService = new ExpressionEditorService();

this.workflowDesigner.Context.Services.Publish<IExpressionEditorService>(this.expressionEditorService);

An expression editor is created when an ExpressionTextBox instance gains focus and is destroyed on losing focus of a valid expression, or on reloading of the designer.

The default expression editor is not available for use in rehosted applications. If the default expression editor is used in a rehosted application, a text box is available for editing. However, custom expression editors can be used in a rehosted application by publishing the IExpressionEditorService in the application.

If you are using an ExpressionTextBox control in a custom activity designer, it is not necessary to create and destroy expression editors using this interface. The ExpressionTextBox class manages this for you.

Methods

CloseExpressionEditors()	Closes all the active expression editors.
CreateExpressionEditor(AssemblyContextControlItem, ImportedNamespaceContextItem, List<ModelItem>, String)	Creates a new expression editor.
CreateExpressionEditor(AssemblyContextControlItem, ImportedNamespaceContextItem, List<ModelItem>, String, Size)	Creates a new expression editor using the specified assemblies, imported namespaces, variables, expression text, and the initial size.
CreateExpressionEditor(AssemblyContextControlItem, ImportedNamespaceContextItem, List<ModelItem>, String, Type)	Creates a new expression editor using the specified assemblies, imported namespaces, variables, expression text, and expression type.
CreateExpressionEditor(AssemblyContextControlItem, ImportedNamespaceContextItem, List<ModelItem>, String, Type, Size)	Creates a new expression editor using the specified assemblies, imported namespaces, variables, expression text, expression type, and the initial size.
UpdateContext(AssemblyContextControlItem, ImportedNamespaceContextItem)	Updates the context for the editing session.