How do I make this method post in html5 canvas.

function sendPontuacao(score):void {
var requestVars = new URLVariables();
requestVars.score = score;
var request = new URLRequest("/system/sendscore");
request.data = requestVars;
request.method = URLRequestMethod.POST;
try {
new URLLoader().load(request);
} catch (e:Error) {
trace(e);
}
}
this.sendPontuacao(1);