HTML5 canvas图像问题(HTML5 canvas Image issue)

 我用HTML5制作游戏，这张图片不会画。 在chrome js控制台中，它说它没有任何问题。 
 
 声明图像： var wall1 = new Image(); 
 
 调用onload： 
 
function render(arg1, arg2, arg3){
    wall1.onload = drawwall(arg1, arg2, arg3);
    wall1.src = "assets/slide.jpg";
}
 
 画墙功能： 
 
function drawwall(numb, dist, hm){
    ctx.drawImage(wall1,numb*4,4,4,height[hm]*3/dist,numb*4,1,4,height[hm]*3/dist);
}
 
 我试过return ctx.drawImage(...并return Function(){ctx.drawImage(...但它仍然无法正常工作。 

I making a game in HTML5 and this image wont draw. In the chrome js console it says there's nothing wrong with it.
 
Declaring the image: var wall1 = new Image();
 
calling the onload:
 
function render(arg1, arg2, arg3){
    wall1.onload = drawwall(arg1, arg2, arg3);
    wall1.src = "assets/slide.jpg";
}
 
Draw wall function:
 
function drawwall(numb, dist, hm){
    ctx.drawImage(wall1,numb*4,4,4,height[hm]*3/dist,numb*4,1,4,height[hm]*3/dist);
}
 
I've tried return ctx.drawImage(... and return Function(){ctx.drawImage(... but it still wont work.

原文：https://stackoverflow.com/questions/29927033