aspnetcore-custom-exception-middleware

various ways to handle exceptions globally in asp.net core web api

middleware

In the context of a HTTP request pipeline, middleware is also commonly referred to as request delegates, which are orchestrated using Run, Use and Map. Using Run will immediately short circuit the request pipeline. Also you can short circuit the pipeline by not calling next parameter.

01-inline middleware

02-middleware in a class

03-simple global exception handling middleware

Don't call next.Invoke after the response has been sent to the client. Changes to HttpResponse after the response has started throw an exception.

For example, changes such as setting headers and a status code throw an exception. Writing to the response body after calling next:

• May cause a protocol violation. For example, writing more than the stated Content-Length.
• May corrupt the body format. For example, writing an HTML footer to a CSS file.

HasStarted is a useful hint to indicate if headers have been sent or the body has been written to.

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04-global exception handling using custom filters

05-global exception handling using app.UseExceptionHandler