750 Chapter 12: ActionScript Dictionary
The object parameter becomes the context in which the properties, variables, and functions in
the
statement(s) parameter are read. For example, if object is my_array, and two of the
properties specified are
length and concat, those properties are automatically read as
my_array.length and my_array.concat. In another example, if object is state.california,
any actions or statements inside the
with action are called from inside the california instance.
To find the value of an identifier in the
statement(s) parameter, ActionScript starts at the
beginning of the scope chain specified by the
object and searches for the identifier at each level
of the scope chain, in a specific order.
The scope chain used by the
with action to resolve identifiers starts with the first item in the
following list and continues to the last item:
• The object specified in the object parameter in the innermost with action.
• The object specified in the object parameter in the outermost with action.
• The Activation object. (A temporary object that is automatically created when a function is
called that holds the local variables called in the function.)
• The movie clip containing the currently executing script.
• The Global object (built-in objects such as Math and String).
To set a variable inside a
with action, the variable must have been declared outside the with
action or you must enter the full path to the Timeline on which you want the variable to live. If
you set a variable in a
with action without declaring it, the with action will look for the value
according to the scope chain. If the variable doesn’t already exist, the new value will be set on the
Timeline from which the
with action was called.
In Flash 5 or later, the
with action replaces the deprecated tellTarget action. You
are encouraged to use
with instead of tellTarget because it is a standard ActionScript extension
to the ECMA-262 standard. The principal difference between the
with and tellTarget actions
is that
with takes a reference to a movie clip or other object as its parameter, while tellTarget
takes a target path string that identifies a movie clip as its parameter, and cannot be used to
target objects.
Example
The following example sets the _x and _y properties of the someOther_mc instance, and then
instructs
someOther_mc to go to Frame 3 and stop.
with (someOther_mc) {
_x = 50;
_y = 100;
gotoAndStop(3);
}
The following code snippet shows how to write the preceding code without using a with action.
someOther_mc._x = 50;
someOther_mc._y = 100;
someOther_mc.gotoAndStop(3);
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