Markup Middleware provides a simple mechanism by which requests for file operations involving Markup Layers can be intercepted and the data being stored and retrieved can be modified, or the request can be rejected altogether without requiring the Developer to write their own Data Provider from scratch. Middleware can be specified as a property of any Markup Data Provider via Web.config MarkupImageDataProvider. This class contains 4 virtual methods which can be overridden, each of which corresponds to a file operation involving Markup Layers. If a MarkupImageDataProvider is configured to use a derivation of this class, the respective method will be called after each read/list operation, or before each update/create operation. The default implementations of these methods do nothing. These methods will be called by the respective methods that perform I/O operations in MarkupFileImageDataProvider and MarkupSqlImageDataProvider. If implementing your own data provider, it is up to your implementation to repect any middleware specified in Web.config.

'Declaration
 
Public Class MarkupArtMiddleware 

'Usage
 
Dim instance As MarkupArtMiddleware

public class MarkupArtMiddleware 

public __gc class MarkupArtMiddleware 

public ref class MarkupArtMiddleware