Foundation of SharePoint 9-Site Page and application page

Some pages in a WSS site, such as the homepage (default. aspx), allowing you to use tools such as SharePoint designer for customization ). the page supporting customization is called site pages. although it provides a great deal of flexibility for customized Site pages, it also has a disadvantage. to support page customization without affecting scalability, WSS must use the page ghosting discussed earlier. however, page customization still has a considerable impact on scalability.

 

Imagine a WSS environment with a web application running thousands of sites. If the administrator of each site uses SharePoint designer to change the homepage of the site, what will happen? Every page in these sites will become unghosted. this forces the front-end server to retrieve each page from the content database separately, negatively affecting scalability. every page has to be parsed and loaded into the memory.

 

Consider the fact that when a website page is customized, a copy will certainly exist in the content database. this brings about a security problem. imagine that a malicious user is given the site set administrator permission to attack by writing Inline code on a custom version of the site page. this security problem is handled by a default WSS policy. This policy is to disable the Inline code contained in the site page. this default policy also enables the site page to run in non-compilation mode, that is, they will not be compiled as DLL.

 

The key point here is that the customized support for site pages brings performance and security issues. as you noted earlier, The WSS architecture provides another type of page called Application page. A key feature of application page is that it does not support customization. therefore, application page can bypass the performance and security issues associated with site page.

 

Standard site configuration page (settings. aspx) is a good example of application page. it can be accessed on any site, and it does not support customization. application page, such as settings. aspx is deployed as a physical file on the file system of the Web Front-End Server. It is deployed in the following path:

C: \ Program Files \ common files \ microsoft shared \ Web Server Extensions \ 12 \ template \ layouts

 

Note: each time WSS creates a web application, the physical path \ layouts directory is mapped to the virtual path _ layouts. This ing mechanism is used, and some additional processing logic is added,WSS RuntimeAny application page can be accessed in the context of any site. for example, if there are three different sites, they can access them in The WSS environment through the following three urls:

Http://Litwareinc.com

Http://Litwareinc.com/sites/Vendors

Http://Litwareinc.com: 1001/sites/Accounting

An application page, such as settings. aspx, can be accessed by adding its relative path within the _ layouts directory to the end of a site's URL. for example, you can access the site setting page by using any of the following three urls:

An application page, such as settings. aspx, which can be accessed by adding its relative path in the _ layouts folder after the site URL. for example, you can use the following URL to access the site settings. aspx.

Http://Litwareinc.com/_layouts/settings.aspx

Http://Litwareinc.com/sites/Vendors/_layouts/settings.aspx

Http://Litwareinc.com: 1001/sites/accounting/_ layouts/settings. aspx

 

At the field level, an application page has only one version, so it can be compiled into a single DLL, and each web application is loaded to the memory only once. you never need to worry about different application pages on different sites. furthermore, application page will not be attacked by users with custom permissions. therefore, WSS does not prevent them from containing Inline code (in-line code ).

 

Application page is widely used by the WSS team to support many features used to create and manage sites and site elements. represents an image of the \ layouts physical folder. you can see that wss3.0 Standard installation includes many different application pages, including settings. aspx

If you open and view an application page of the standard WSS, you will see that it is linked to a master page under the _ layouts directory, called application. master. later, we will introduce how to create a custom application page. when you create an application page of your own, you may want to connect to the application like they do. master.

 

Let's summarize the differences between site page and application page. site Page supports page customization. for example, the home page and other pages associated with the list and document library, such as allitems. aspx, newform. aspx, and editform. aspx. in fact, Site Page supports customization, but it also affects performance and scalability. site page does not support Inline code because WSS enforces a default security policy.

 

Application page does not support customization, which also provides two advantages over site page. first, any application page will be compiled into a single DLL file, so their performance and scalability are better than Site Page. second, the application page allows Inline code.