我一直在使用Pieter的解决方案，直到我意识到它在Mono中不起作用。当用管道输入检索 Console.KeyAvailable 时，Mono不会引发异常。因此，这种方法没有帮助。

I've been using Pieter's solution for a while until I realised it doesn't work in Mono. Mono doesn't throw an exception when retrieving Console.KeyAvailable with piped input, so that approach doesn't help.

但是，从.NET 4.5开始， Console 实际上提供了一个新的字段 IsInputRedirected 删除阴影和不必要的 try / catch ：

However, as of .NET 4.5, Console actually provides a new field IsInputRedirected which makes this a lot simpler, removes the obscurity and the unnecessary try/catch:

TextReader reader;

if (args.Length > 1) {
    reader = new StreamReader(new FileStream(args[1], FileMode.Open));
} else {
    if (Console.IsInputRedirected) {
        reader = Console.In;
    } else {
        Console.WriteLine("Error, need data");
        return;
    }
}

Process(reader);