Beginning Ajax With ASP.NET (2006).pdf

Chapter 8
Listing 8-2: RegisterTypeForAjax Definition in /Ajax/Utility.cs
01. public static void RegisterTypeForAjax(Type type)
02. {
03. System.Web.UI.Page page =
(System.Web.UI.Page)System.Web.HttpContext.Current.Handler;
04. RegisterTypeForAjax(type, page);
05. }
06.
07. public static void RegisterTypeForAjax(Type type, System.Web.UI.Page page)
08. {
09. RegisterCommonAjax(page);
10. string path = type.FullName + “,” + type.Assembly.FullName.Substring(0,
type.Assembly.FullName.IndexOf(“,”));
11. if(Utility.Settings.UseAssemblyQualifiedName) path =
type.AssemblyQualifiedName;
12.
13. if(Utility.Settings != null &&
Utility.Settings.UrlNamespaceMappings.ContainsValue(path))
14. {
15. foreach(string key in Utility.Settings.UrlNamespaceMappings.Keys)
16. {
17. if(Utility.Settings.UrlNamespaceMappings[key].ToString() == path)
18. {
19. path = key;
20. break;
21. }
22. }
23. }
24.
25. RegisterClientScriptBlock(page, “AjaxType.” + type.FullName,
“”);
26. }
The first thing that happens in the RegisterTypeForAjax() method is that the Utility.Register
CommonAjax() method is called on line number 09. The RegisterCommonAjax() method is responsible
for adding script references to the prototype, core, and converter files. This method makes sure to
register these files only once per page, even if you’re registering multiple types. You’ll see how this is
done shortly with the inspection of the Settings object.
At this point, you know that the prototype, core, and converter scripts have been registered, and
you’re ready to move on and create a reference to your own type. Line 10 creates a string that consists of the
type’s fully qualified name and the assembly that the type is in. This results in the /Chapter7_OnLoading,
App_Web_rjv9qbqt found in line 2 in Listing 8-1. This value is checked against a HashTable named
Utility.Settings.UrlNamespaceMappings. If the value is found, line 20 calls break, and the method
replaces the type name with the mapped name. You’ll take look at this UrlNameSpaceMappings shortly.
If the value is not found, then you know to simply use the type name as the script source.
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