c#net怎么将记录写入到指定文本文件中

c#.net如何将记录写入到指定文本文件中？

C# code

private void SaveToFile(){            string result =                 this.Barcode1 + "," +                this.Barcode2 + "," +                this.SNoCount + "," +                this.TimeStamp;}

C# code

System.IO.StreamWriter sw = new System.IO.StreamWriter(@"C:\logfile.txt",true);sw.WriteLine(result);sw.Close();
[解决办法]
System.IO.StreamWriter sw = new System.IO.StreamWriter(@"C:\logfile.txt",true);
sw.WriteLine(result);
sw.Flush();
sw.Close();

or

File.WriteAllText("c:\text.txt",text);
[解决办法]
探讨

我在file下面没有找到writeAllText这个方法吗？ 
IO包已经加了