c#文件流汇总

       public static void InsertData(string str)
        {
            string filePath = @"f:\1.txt";

            if (!File.Exists(filePath))
            {
                using (FileStream fs = new FileStream(filePath, FileMode.Create, FileAccess.Write))
                { 
                    StreamWriter sw = new StreamWriter(fs,Encoding.GetEncoding("GB2312"));
                    sw.Write(str);
                    sw.Close();
                    fs.Close();
                }
            }
            //以追加方式写入数据，并且只定编码格式，默认是UTF-8（中文乱码）
            using(StreamWriter tsw = new StreamWriter(filePath,true,Encoding.GetEncoding("GB2312")))
            {
                tsw.Write(System.Environment.NewLine);//换行符
                tsw.Write(str);
                tsw.Close();
            }
        }