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Dispatching requests and responses
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The dispatcher components in the Web application module control the flow of the application. The dispatchers determine how to handle certain types of HTTP request messages by examining the HTTP request.
The adapter dispatcher component (TAdapterDispatcher) looks for a content field, or a query field, that identifies an adapter action component or an adapter image field component. If the adapter dispatcher finds a component, it passes control to that component.
The Web dispatcher component (TWebDispatcher) maintains a collection of action items (of type TWebActionItem) that know how to handle certain types of HTTP request messages.... more 
When responding to a request, the Web dispatcher (TWebDispatcher) searches through its list of action items for one that:
  • matches the PathInfo portion of the target URL's request message, and
  • can provide the service specified as the method of the request message.
It accomplishes this by comparing the PathInfo and MethodType properties of the TWebRequest object with the properties of the same name on the action item.
When the dispatcher finds the appropriate action item, it causes that action item to fire. When the action item fires, it does one of the following:
  • Fills in the response content... more 
One reason to use WebSnap for your Web server application development is that WebSnap components automatically handle HTML requests and responses. Instead of writing event handlers for common page transfer chores, you can focus your efforts on your business logic and server design. Still, it can be helpful to understand how WebSnap applications handle HTML requests and responses. This section gives you an overview of that process.
Before handling any requests, the Web application module initializes the Web context object (of type TWebContext). The Web context object, which is accessed by calling the global WebContext function, provides global access to... more 
When the page dispatcher receives a client request, it determines the page name by checking the PathInfo portion of the target URL's request message. If the PathInfo portion is not blank, the page dispatcher uses the ending word of PathInfo as the page name. If the PathInfo portion is blank, the page dispatcher tries to determine a default page name.
If the page dispatcher's DefaultPage property contains a page name, the page dispatcher uses this name as the default page name. If the DefaultPage property is blank and the Web application module is a page module, the page dispatcher uses... more 
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