图片切割(裁剪)系统 .NET版 作者声明：

首先js是不能操作客户端文件的(除非特殊情况)，所以图片的切割必须在后台处理，对于客户端的图片可以先上传再切割或者把图片和切割参数一起传递到服务器再处理（上传文件不在本次讨论范围，请自行修改）；还有是通过客户端传递的参数来处理图片，确实能得到展示图或预览图的效果。-Cut (cut) system.NET edition author statement:

First, JS can not operate the client-side files ( unless special circumstances), so the picture cut to the background processing, for the client the pictures to upload the pictures and then cutting or cutting parameters passed to the server with the reprocessing ( upload file is not in the scope of this discussion, please modify )　and by the client the parameters passed to deal with pictures, really can get display chart or map results.