What’s the use of "GLOBAL.ASAX" file in ASP.NET?
The Global.asax file in ASP.NET is an optional file that provides a way to handle global application-level events and settings. It serves as the entry point and central configuration file for an ASP.NET application. The main uses of the Global.asax file include:
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Application-level events: The Global.asax file allows you to handle various events that occur at the application level, such as Application_Start, Application_End, Session_Start, Session_End, and Application_Error. These events provide hooks to execute custom code during different stages of the application's lifecycle. For example, you can use Application_Start to initialize application-wide resources or configure application settings.
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Error handling: The Application_Error event in Global.asax allows you to catch unhandled exceptions that occur within your application. You can implement custom error handling logic to log or display error messages, redirect users to error pages, or perform any necessary cleanup tasks. This event is useful for centralized error handling and providing a consistent user experience.
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Session management: The Session_Start and Session_End events in Global.asax are triggered when a user's session starts and ends, respectively. You can use these events to perform actions like initializing session-specific data or releasing resources associated with a session.
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URL routing: The Global.asax file can be used to define custom URL routing rules. By implementing the Application_Start event, you can register routes that map specific URLs to controllers and actions in ASP.NET MVC or to specific handlers in ASP.NET Web Forms. This enables you to have clean and meaningful URLs for your application.
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Application-wide configuration: The Global.asax file can be used to set global configuration settings for your application. For example, you can specify custom error pages, define HTTP modules, configure authentication and authorization settings, or establish application-wide culture and globalization settings.
In summary, the Global.asax file in ASP.NET allows you to handle application-level events, implement error handling, manage sessions, define URL routing rules, and set global configuration settings. It provides a central place to handle various aspects of your application's behavior and lifecycle.