Question

假设我有一个图像/site/image1.jpg将它绘制到画布上它会是这样的。

var image = new Image();
image.src = "/site/image1.jpg";
image.onload = function(){
    context.drawImage(image,x,y);
}

假设我的互联网连接太慢，我怎么知道图片已经在画布上绘制了？

感谢。

Answer 1

要进行锻炼，如果图像已被绘制，请保留标记或标记图像。

var image = new Image();
image.src = "blah.foo";
image.drawn = false;  // Add a property to indicate if the image has been drawn
image.onload = function(){
    ctx.drawImage(image,0,0);
    image.drawn = true;  // flag it as drawn
}
// then later you if you want to know if its been drawn
if(image.drawn){
    console.log("Yes its been drawn.");
}

如何确定是否已在HTML Canvas中绘制Image

1 个答案: