DataURL与File,Blob,canvas对象之间的互相转换的Javascript (未完)

canvas转换为dataURL (从canvas获取dataURL)

var dataurl = canvas.toDataURL('image/png');
var dataurl2 = canvas.toDataURL('image/jpeg', 0.8);

转:https://blog.csdn.net/cuixiping/article/details/45932793