Apple WebObjects 3.5 Manuel d'utilisateur télécharger pdf (Page 175)

WebScript Language Elements

175

Explicitly specifying a class in a variable or method declaration is called

static typing.

Because variables and return values are always objects, the only supported

data types are classes. You can specify any class that your application

recognizes when you statically type a variable or a method. For example,

each component in your application is a class, so you can do this:

CarPage *carPage = [[self application] pageWithName:"CarPage"];

Also, the default application executable used to run your application

contains the deﬁnitions of classes from the Foundation, WebObjects, and

Enterprise Objects frameworks, so these declarations are valid:

NSString *myString; //Foundation classes

WOContext *theContext; //WebObjects classes

EOEditingContext *editingContext; //Enterprise Objects classes

Plus, if you’re writing a component that uses database access, your

application has an EOModel ﬁle that translates tables in your database into

objects. You can specify any entity named in that model ﬁle as a class. For

example:

Movies *moviesEntity; //entities from your eomodel

Static typing is supported so that WebObjects Builder can correctly parse

your script ﬁle and help you decide which variables you can correctly bind

to certain dynamic elements. (For more information on this, see the online

book WebObjects Tools and Techniques.) As far as WebScript is concerned, all

variables are of type

id.

Note: WebObjects performs absolutely no type checking. The following is

valid WebScript:

NSNumber *aNumber = @"Wait! I’m a string, not a number!";

NSString *aString = 1 + 2;

Statements and Operators

WebScript supports most of the same statements and operators that C

supports, and they work in much the same way. This section describes only

the differences between statements and operators in C and statements and

operators in WebScript.

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Apple WebObjects 3.5 Manuel d'utilisateur Page 175