简单IO操作实例

               DirectoryInfo theFolder = new DirectoryInfo(textBox1.Text);
                if (theFolder == null) return;
                var newFileTxt = textBox1.Text + "\\" + string.Format("{0:yyyyMMddHHmmssffff}", DateTime.Now) + ".txt";
                StreamWriter writer = new StreamWriter(newFileTxt);
                foreach (FileInfo f in theFolder.GetFiles().Where(f => f.FullName.Contains(".sql")))
                {
                    StreamReader reader = new StreamReader(f.FullName,Encoding.Default);
                    string line = "--" + f.Name;
                    while (line != null)
                    {
                        writer.WriteLine(line);
                        line = reader.ReadLine();
                    }
                    reader.Close();
                }
                //writer.Flush();//清理缓冲区，调用后可以继续写入
                writer.Close();