Using System.IO;string fileStr = "";Using(StreamReader sr = new StreamReader(路径)){while(!sr.EndOfStream){string line = sr.ReadLine();if(line.StartsWith("BLC4")){str += string.Format("BLC4,{0},{1},...\r\n",textBox1.Text,textBox2.Text...);}else{str += line + "\r\n";}}}File.WriteAllText(路径,str);
