[]怎么才能像HTML5中那样直接操作Canvas

如下代码，看不到我想画出来的矩形和文本var canvas:HTMLCanvas = Browser.canvas;
var ctx:Context = canvas.getContext();
ctx.fillStyle = "red";
ctx.fillRect(120, 10, 150, 150,"red");
ctx.fillText("texttt",100,100,"","#ffffff","center");
console.log("draw complete");