Canvas----与Image的转换

Image放入画布

// Converts image to canvas; returns new canvas element
function imageToCanvas(image) {
	//image is img element object
	//create canvas object
	var canvas = document.createElement("canvas");
	canvas.width = image.width;
	canvas.height = image.height;
	canvas.getContext("2d").drawImage(image, 0, 0);
	return canvas;
}

Canvas 转为Image

// Converts canvas to an image
function canvasToImage(canvas) {
	//param canvas is element object
	var image = new Image();//img object
	image.src = canvas.toDataURL("image/png");
	return image;
}
/*
1.
2.
canvas.toDataURL("image/png")就是第二种
*/