System.Design 2.0.0.0 System.Object

A custom expression editor sheet lets a developer set properties on a custom expression at design-time. Control property values can be set using expression strings; the expression strings are evaluated at run time by an expression builder and at design time by an expression editor.

When you browse the property for a control in the design-time properties grid, the visual designer displays a dialog box to set expressions that provide the value for a control property. You can select the expression type based on a list of expression prefixes. When you select an expression prefix from the list, the visual designer uses the associated and objects to evaluate and convert the expression string based on the syntax for that type of expression. The visual designer uses expression editor sheet properties to prompt for one or more strings that combine into the custom expression string.

Typically, to supply a new expression type at design time, you define a unique expression prefix and provide custom and implementations. Optionally, you can provide a custom implementation that defines properties that are used to form the expression. To associate an expression prefix with an expression builder and an expression editor, apply the attribute and an attribute to the custom class, and then configure the expression prefix for an expression builder in the expressionBuilders element in the Web configuration file.

The default implementation of the method returns a basic editor sheet, which uses a single input string to form the expression. Custom expression editors that are derived from the can override the method to return a custom editor sheet implementation. Typically, a custom editor sheet contains multiple properties that are used to build the expression string. The method returns the resulting expression string based on the current expression properties.

For example, the class derives from the class and provides an implementation for evaluating and associating a resource string reference with a control property at design time. The class is associated with the expression prefix Resources and the implementation. The method returns a , which defines the individual properties that form a resource reference expression.

When you inherit from the class, you must override the following members:

The method to return a custom editor sheet implementation.

The constructor to implement custom initialization actions for your expression editor sheet implementation.

Represents a design-time editor sheet for a custom expression. This class must be inherited.

- Constructor

  Because the class is abstract, you cannot create an instance of an directly using the constructor.

  Initializes a new instance of the class.

  A service provider implementation supplied by the designer host, used to obtain additional design-time services.
  2.0.0.0
- Method
  System.String

  A custom expression editor sheet contains design-time settings for multiple expression properties, which are combined to form an expression string. Control property values can be set using expression strings; the expression strings are evaluated at run time by an expression builder.

  The method returns an expression string that is built from the current expression properties. The visual designer allows you to set the expression sheet properties, and then calls the method to get the expression string and set the control property value.

  When overridden in a derived class, returns the expression string that is formed by the expression editor sheet property values.

  The custom expression string for the current property values.

  2.0.0.0
- Property
  System.Boolean To be added.

  This base implementation always returns true.

  Gets a value that indicates whether the expression string is valid.

  2.0.0.0
  System.ComponentModel.Browsable(false)
- Property
  System.ComponentModel.Browsable(false)
  System.IServiceProvider To be added.

  Use the constructor to set the implementation for a custom expression editor sheet.

  The property can be used to access services that are provided by the designer host. For example, call the method with the interface to access project items, documents, or configuration file details that are provided through the visual designer.

  Gets the service provider implementation that is used by the expression editor sheet.

  2.0.0.0