MACROMEDIA FLASH MX, Справочник

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1008 Chapter 2: ActionScript Language Reference
Instead of using
with()
, you can use direct paths. If you find that paths are long and
cumbersome to type, you can create a local variable and store the path in the variable, which you
can then reuse in your code, as shown in the following ActionScript:
var shortcut = this._parent._parent.name_txt;
shortcut.text = "Hank";
shortcut.autoSize = true;
For more information on best practices in writing code and code readability, see Chapter 3,
“Avoiding the with statement,” on page 87 of Using ActionScript in Flash .
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
statement.
someOther_mc._x = 50;
someOther_mc._y = 100;
someOther_mc.gotoAndStop(3);
The
with
statement is useful for accessing multiple items in a scope chain list simultaneously. In
the following example, the built-in
Math
object is placed at the front of the scope chain. Setting
Math
as a default object resolves the identifiers
cos
,
sin
, and
PI
to
Math.cos
,
Math.sin
, and
Math.PI
, respectively. The identifiers
a
,
x
,
y
, and
r
are not methods or properties of the
Math
object, but because they exist in the object activation scope of the function
polar()
, they resolve
to the corresponding local variables.
function polar(r:Number):Void {
var a:Number, x:Number, y:Number;
with (Math) {
a = PI*pow(r, 2);
x = r*cos(PI);
y = r*sin(PI/2);
}
trace("area = "+a);
trace("x = "+x);
trace("y = "+y);
}
polar(3);
The following result is displayed in the Output panel.
area = 28.2743338823081
x = -3
y = 3
See also
tellTarget