解决Web上头像裁剪主要存在的知识点： 图片上传 上传后的图片缩放处理 通过在前台裁剪得到图片的x，y坐标和宽度、高度，交由后台自动裁剪图片 -Web address on the knowledge there head cut key point: image upload images upload resized images obtained by cutting in front of x, y coordinates and width, heig

对图片进行裁剪,其中包含几种方式，例如网络图片(Cut the pictures, which include several ways, such as network pictures)