Canvas讀取圖片並畫入畫布

function load_img(i){

cvs = document.getElementById("cvs");

ctx = cvs.getContext("2d");

var x=0;

var y=0;

var img=new Image();

img.src="images/map/1/"+i+".png";

img.onload=function(){

ctx.drawImage(this,x,y,img.width,img.height);

if (i<15){

return load_img(i+1);

}

}

}

<canvas id="cvs" width="800" height="600" draggable="true" style="position: absolute; left: 0px; top:0px;"></canvas>