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This article mainly introduces "what is the execution method of the ASP.NET processor". In the daily operation, I believe that many people have doubts about the execution method of the ASP.NET processor. The editor consulted all kinds of materials and sorted out the simple and easy-to-use operation methods. I hope it will be helpful to answer the doubts about "what is the execution method of the ASP.NET processor?" Next, please follow the editor to study!

How ASP.NET Runtime uses HTTP handlers

Believe it or not, ASP.NET implements a lot of its own functions using HTTP requests. ASP.NET uses handlers to process .aspx, .asmx, .soap, and other ASP.NET files.

Here is a snippet from the machine.config file:

< httpHandlers > < add verb= "*" path= "trace.axd" type= "System.Web.Handlers.TraceHandler" / > < add verb= "*" path= "* .aspx" type= "System.Web.UI.PageHandlerFactory" / > < add verb= "*" path= "* .ashx" type= "System.Web.UI.SimpleHandlerFactory" / > < add verb= "*" path= "* .config" type= "System.Web.HttpForbiddenHandler" / > < add verb= "GET,HEAD" path= "*" type= "System.Web.StaticFileHandler" / >. . . . . . . . . . . . < / httpHandlers >

In the configuration information above you can see that all requests for .aspx files are handled by the System.Web.UI.PageHandlerFactory class. Similarly, all requests for .config files and other files, which cannot be directly accessed by the client, are handled by the System.Web.HttpForbiddenHandler class. As you may have guessed, when accessing these files, the class simply returns an error message to the client.

Execute the HTTP handler

Now you will see how to implement a HTTP handler. So what does our new processor do? As I mentioned earlier, handlers are mostly used to add new functionality to the Web server; therefore, I will set up a handler to handle the new file type-- files with a .15seconds extension. After we have set up this handler and registered it in our Web application's web.config file, all requests for the .15seconds file will be processed by this new handler.

You may be considering how to use this handler. What if you want to introduce a new server scripting language or dynamic server files (such as asp, aspx)? You can write your own handler for it. Similarly, what if you want to run Java Mini Program, JSP, and other server-side Java components on IIS? One way is to install some ISAPI extensions (such as Allaire or Macromedia Jrun). You can also write your own HTTP handlers. Although this is a complex transaction for third-party vendors such as Allaire and Macromedia, it is an attractive choice because their HTTP processing has access to all the new features exposed by the ASP.NET runtime.

Implementing our HTTP handler consists of the following steps:

1. Write a class that implements the IHttpHandler interface.

two。 Register the handler in the web.config or machine.config file.

3. Map the file extension (.15seconds) to the ASP.NET ISAPI extension DLL (aspnet_isapi.dll) in the Internet service manager.

* step

Create a new C# class library project in Visual Studio.NET and name it "MyHandler". Visual Studio.NET will automatically add a class called "Class1.cs" to the project. Rename it to "NewHandler"; open the class in the code window and change the name of the class and constructor to "NewHandler".

Here is the code for the NewHandler class:

Using System; using System.Web; namespace MyHandler {public class NewHandler: IHttpHandler {public NewHandler () {/ / TODO: add construction logic here} # region Implementation of IHttpHandler public void ProcessRequest (System.Web.HttpContext context) {HttpResponse objResponse = context.Response; objResponse.Write ("< html > < body > < H2 > Hello 15Seconds Reader"); objResponse.Write ("< / body > < / html >") } public bool IsReusable {get {return true;}} # endregion}}

You can see in the ProcessRequest method that the HTTP handler accesses all the ASP.NET internal objects passed to it as parameters through the System.Web.HttpContext object. To implement the ProcessRequest method, you simply extract the HttpResponse object from the context object and send some HTML to the client. Similarly, IsReusable returns true, indicating that this handler can be used repeatedly to process other HTTP requests.

We compile the above code and put it in the bin directory of the webapp virtual directory.

Step two

Register the handler in the web.config file by adding the following text:

< httpHandlers > < add verb= "*" path= "* .15seconds" type= "MyHandler.NewHandler,MyHandler" / > < / httpHandlers >

Step three

Now that we have established a handler for processing the new extension file, we also need to tell IIS this extension and map it to ASP.NET. If you try to access the Hello.15seconds file without performing this step, IIS will simply return the file instead of passing it to the ASP.NET runtime. The result is that the HTTP handler will not be called.

Run the Internet service manager, right-click the default Web site, select Properties, move to the Home directory option page, and click the configure button. The application configuration dialog box pops up. Click the add button and enter the path to the aspnet_isapi.dll file in the executable field and .15seconds in the extension field. The other fields do not need to be processed; the dialog box is as follows:

Click the confirm button to close the application configuration and default Web site properties dialog box.

Now we run Internet Explorer and type url: http://localhost/webapp/hello.15seconds, and the page we see is as follows:

At this point, the study on "what is the execution method of the ASP.NET processor" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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