creator 3.4.2 画布bug

[su_jiehao]

    const canvas: HTMLCanvasElement = document.getElementById("GameCanvas") as HTMLCanvasElement;
    console.log("canvas====", canvas)
    const ctx:CanvasRenderingContext2D = canvas.getContext("2d")

为啥这里打印ctx是null，我用网页来写这段代码是没问题的，返回CanvasRenderingContext2D