Dynamic | server | design | server-side processing, ASP is a relatively new technology to generate dynamic Web pages. What does a dynamic page mean? The progress of client-related functionality is not considered for the moment, nor is it discussed with client script, Java applets, Dynamic HTML, or ActiveX controls. The dynamic page here is specifically the page that the server responds to the client request, and the pages generated each time may be different depending on the situation.
To give a simple example, create a page that contains only the current date and time. Each time the page is requested, a different value is displayed because the date and time depend on the server's clock, or on a resource that provides the date and time (for example, a stand-alone server or a standard clock from the Internet). Of course, dynamic pages are actually much more complicated than this, perhaps displaying the current value of the database record or a summary of the mail messages waiting on the mail server. It is important that the server not only read an unformatted HTML page, or text files on a disk, but also send them to customers, and you must do some work to create the page.
Internet Server Application Programming interface
The traditional technique is to use an interface with a Web server, which is called the Internet Server Application programming interface (Internet Servers application programming Interface,isapi).
ISAPI can be used to execute other applications that use the C-style stdin and stdout data flow functions to read the values requested by the client and create a response from the Web server. All that an ISAPI application must do is write the text and HTML of the corresponding results page and output it to the Web server through the STDOUT function. In fact, the things that are really done inside an ASP dll are more object-oriented.
IIS runs the ISAPI application and script interpreter since it started. It provides a special interpreter dynamic link library, giving access to the server's request and response to another method, although subject to a certain limit. It is implemented through the server-side include directives because they are executed on the server and the results are contained in the response that is sent to the client. This feature is implemented in IIS through a dynamic link library named Ssinc.dll. By default, IIS maps to this dynamic link library any page that has a file name extension of. shtml,. shtm, or. stm. You can see this mapping by opening the Properties dialog box for the Default Web site and clicking the configuration button in application setting.
In this way, pages with these mapped file extensions will be sent to ssinc.dll for processing. As a result, all server-side include statements are executed on the page, and the results, if any, are inserted into the server's response, which is inserted into the page that the client receives.
Because these files are mapped to Ssinc.dll files rather than to the ASP Dynamic link library (asp.dll), all ASP code on these pages will be ignored and routed to the client in its original state, and the client will be able to see the scripts. However, there is a way to avoid this in the version of ASP 3.0, which is studied later when discussing the execute and transfer methods of the server object.
