Dot Syntax
In ActionScript, a dot ( . ) is used to indicate the properties or methods related to an object or movie clip. It is also used to identify the target path to a movie clip, variable, function, or object. A dot syntax expression begins with the name of the object or movie clip followed by a dot, and ends with the element you want to specify.
For example, the _x movie clip property indicates a movie clip’s x axis position on the Stage. The expression ballMC._x refers to the _x property of the movie clip instance ballMC .
As another example, submit is a variable set in the form movie clip, which is nested inside the movie clip shoppingCart . The expression shoppingCart.form.submit = true sets the submit variable of the instance form to true .
Expressing a method of an object or movie clip follows the same pattern. For example, the play method of the ballMC instance moves the playhead in the Timeline of ballMC , as in the following statement:
ballMC.play();
Dot syntax also uses two special aliases, _root and _parent . The alias _root refers to the main Timeline. You can use the _root alias to create an absolute target path. For example, the following statement calls the function buildGameBoard in the movie clip functions on the main Timeline:
_root.functions.buildGameBoard();
You can use the alias _parent to refer to a movie clip in which the current movie clip is nested. You can also use _parent to create a relative target path. For example, if the movie clip dog is nested inside the movie clip animal , the following statement on the instance dog tells animal to stop:
_parent.stop();