How to make actionscript run once?

When I add actionscript to 开发者_C百科a Flash movie, it runs every time the movie enters a new loop. How do I make it run only once, when the movie has finished loading?

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Just set a flag telling you if the script has already executed. Like this;

var done:Boolean;
if (!done) {

    // any code here will run only once.

    done=true;
}