HttpPostedFileBase imgFile = Request.Files[0];//获取到文件流

 filename = imgFile.FileName;

                imgFile.SaveAs(Server.MapPath("../Test/" + filename));//保存到本地

 var archive = ArchiveFactory.Open(Server.MapPath("../Test/" + filename));//通过Server.MapPath找到文件的绝对路径

            foreach (var entry in archive.Entries)

            {

                if (!entry.IsDirectory)//开始解压

                {

                    entry.WriteToDirectory(Server.MapPath("../Test/"), ExtractOptions.ExtractFullPath | ExtractOptions.Overwrite);//解压地址也是要绝对路径的

                }

            }