+ +
+

Application Flow Chart

+

The following graphic illustrates how data flows throughout the system:

+

CodeIgniter application flow

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    +
  1. The index.php serves as the front controller, initializing the base +resources needed to run CodeIgniter.
    2. +
  2. The Router examines the HTTP request to determine what should be done +with it.
    3. +
  3. If a cache file exists, it is sent directly to the browser, bypassing +the normal system execution.
    4. +
  4. Security. Before the application controller is loaded, the HTTP +request and any user submitted data is filtered for security.
    5. +
  5. The Controller loads the model, core libraries, helpers, and any +other resources needed to process the specific request.
    6. +
  6. The finalized View is rendered then sent to the web browser to be +seen. If caching is enabled, the view is cached first so that on +subsequent requests it can be served.
    7. +
+
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