What is the difference between handler and module in asp.net

HTTP Modules are plugged into the life cycle of a request. So when a request is processed it is passed through all the modules in the pipeline of the request. So generally http modules are used for:. Statistics and Logging : Since modules are called for every request they can be used for gathering statistics and for logging information. Custom header : Since response can be modified, one can add custom header information to the response.

Difference between ASP. Reeta Singh Lodhi Updated date Feb 22, Based on the extension of the file, the appropriate HTTP Handlers gets loaded which is mapped to the extension and is responsible for processing the ASP. NET request. This interface provides one method ProcessRequest and a property IsReusable. Now add a simple text file with extension ". It should look like the following-. So in simple words, an HttpHandler is frequently associated with a specific extension, and a practical usage includes dynamic image generation or modification.

Now let's explore the HttpModule. HttpModule is another part of request processing of ASP. In a single request processing, there can be more than one modules which gets executed. HttpModules take part in processing of the request by handling the Application events. There are number of events which you can handle during the HttpModule processing. You can also create custom HttpModules. This interface provides two method -.

Now call the same file in a browser "Hello. You will find a requestLog. So in simple words, an HttpModule will execute for every request of your application, irrespective of the extension used.

Http Modules are generally used for security, statistics, logging etc. This article has been editorially reviewed by Suprotim Agarwal. Error : This event occurs when an unhandled exception occurs. If you want to write a custom error handler module, synchronize this event. It can be declared at the computer, site, or application level. The IHttpModule interface has two methods with the following signatures:. Handlers are used to process individual endpoint requests.

Handlers enable the ASP. Unlike modules, only one handler is used to process a request. All handlers implement the IHttpHandler interface, which is located in the System. Subdirectories inherit these settings. The IHttpHandler interface has one method and one property with the following signatures:. Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services.

Privacy policy. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Original product version: ASP. HTTP modules overview Modules are called before and after the handler executes.

Available events that HTTP modules can synchronize with An HttpApplication class provides a number of events with which modules can synchronize.