摘要： public class FileDownload : IDisposable readonlystaticstringMULTIPART_BOUNDARY="<q1w2e3r4t5y6u7i8o9p0>";readonlystaticstringMULTIPART_CONTENTTYPE="multipart/byteranges;boundary="+MULTIPART_BOUNDARY;readonlystaticstringHTTP_HEADER_Content_Disposition="Content-Dispos 阅读全文