Console.WriteLine("Hello World");
FileStream fs1 = new FileStream("Test.txt", FileMode.Create);
// First, save the standard output.
TextWriter tmp = Console.Out;
StreamWriter sw1 = new StreamWriter(fs1);
Console.SetOut(sw1);
Console.WriteLine("Hello file");
Console.SetOut(tmp);
Console.WriteLine("Hello World");
sw1.Close();
设置到FileStream就是输出到文本文件,设置为Console.Out就是输出到命令行窗口