2023年11月10日记录一下，在自己的商品库项目里用到的，之前的代码没有关闭文件流，导致想在上传到七牛云后再删除本地图片就报错了，删除不了，改了一下，关闭了文件流，然后就可以删除了，记得引用nuget: Qiniu.SDK

//using Qiniu.Util;
//using Qiniu.Storage;
string AccessKey = "WB-23oGbtMRULmI1n5345320zbdk2O";
string SecretKey = "cJRT2FAUG9nsG25325326nu3x27nz3D";
string Bucket = "niunan-net";
Mac mac = new Mac(AccessKey, SecretKey);
PutPolicy putPolicy = new PutPolicy();
putPolicy.Scope = Bucket;
putPolicy.SetExpires(3600);
string jstr = putPolicy.ToJsonString();
string token = Auth.CreateUploadToken(mac, jstr);
Config config = new Config();
config.Zone = Zone.ZoneCnSouth;
config.UseHttps = false;
config.UseCdnDomains = true;
FormUploader fu = new FormUploader(config);
Stream s = new System.IO.FileInfo(tpath).OpenRead();
var result = await fu.UploadStream(s, filename_upload, token, null);
s.Dispose();
s.Close();
log.Info($"上传图片到七牛云，文件名【{filename_upload}】，上传结果\r\n{result.Text}\r\n\r\n\r\n");