IO文本操作

StreamWriter sw = new StreamWriter(url, “false 覆盖，true 追加”, Encoding.UTF8);
sw.Write(“内容”);
sw.Close();

FileInfo info = new FileInfo("路径");
            FileStream fs = new FileStream(pash, FileMode.OpenOrCreate, FileAccess.Read);
            byte[] b = new byte[info.Length];
            fs.Read(b, 0,b.Length);
            UTF8Encoding utf = new UTF8Encoding();
            string st = utf.GetString(b);
            fs.Close();
            //st 文本内容