Microsoft Sharepoint Products and Technologies Resource Kit eBook

1004 Part IX: Maintaining a Server in Windows SharePoint Services
page is rendered by the SafeMode parser that is part of the Web Part infrastructure.
The following steps are taken during this page rendering process:
■ Retrieves the page’s collection of Web Parts, determines whether the page is in
personal or shared view, and resolves personalization and customization considerations.
■ Verifies that every part in a Web Part Zone is in the SafeControls list. If a page
is parsed by the SafeMode parser all server controls, even those that are not a
part of a Web Part Zone, are validated against the SafeControls list, which is
located in the Web.config file.
After this, the infrastructure creates each Web Part until all the parts are rendered
on the page and the page is returned to the requestor.
Web Part Rendering
Rendering a Web Part is handled by the standard ASP.NET rendering process. The
Render method of the WebPart class is inherited from the System.Web.UI.Control
class and is used by the Microsoft.SharePoint.WebPartPages.WebPart base class to
add the frame around the content provided by the Web Part. The Render method
also calls the RenderWebPart method so the Web Part can generate the HTML that is
rendered inside the Web Part frame. Although the Render method on the base class
is defined as overridable, it is not recommended that you do so. Instead, implement
any rendering for the Web Part in the RenderWebPart method. The entire rendering
process is shown in Figure 37-1.
ASPX Page
Web Part
F37xr01.bmp
Figure 37-1 Rendering Web Part Pages and Web Parts
Page States Explained
Request
ASP.NET starts
page render
WebPart.Render()
CustomPart.RenderWebPart()
We have seen that Web Part Pages can be in different states. The main reasons for
SharePoint to store some templates in the file system (ghosted) and some in the
database (unghosted) have to do with security and scalability.