Beginning Web Development, Silverlight, and ASP.NET AJAX

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CHAPTER 14 ■ JAVASCRIPT PROGRAMMING WITH ASP.NET AJAX
runtime, and thus the underpinnings for much of the object-oriented functionality in
your class are available. However, you have to be careful about how you declare your
class to the page. You can do it within a tag that references the saved Boat.js, but
you will end up with some problems if the browser tries to parse your class definition
before it parses the supporting classes. In this case, it will not recognize the Type class in
the very first line, and you’ll get an error.
A better approach is to register your class with the ScriptManager, and have it manage
downloading your script to the client.
When you place a ScriptManager on your page, you can select it in Visual Studio
and inspect its Scripts collection using the Property Editor. This will call up the
ScriptReference Collection Editor. On here, you can click Add to add a new Scripts
reference and specify the path of the new reference to the script that you want to
download—in this case, Boat.js (see Figure 14-1).
Figure 14-1. Adding a script reference to the ScriptManager
This will create a declaration on your page that looks like this: