Is it possible to intercept Console output?

Question

I call a method, say, FizzBuzz(), over which I have no control. This method outputs a bunch of stuff to the Console using Console.WriteLine.

Is it possible for me to intercept the output being generated by the FizzBuzz method? Note that my application is a Console app itself.

Answer 1

Yes, very much possible:

var consoleOut = new StringWriter(); Console.SetOut(consoleOut); Console.WriteLine("This is intercepted."); // This is not written to console File.WriteAllText("ConsoleOutput.txt", consoleOut.ToString()); 

Later on if you want to stop intercepting the console output, use modification below:

var stdOut = Console.Out; // Above interceptor code here.. Console.SetOut(stdOut); // Now all output start going back to console window 

Or the OpenStandardOutput does the same without the need to save the standard stream first:

// Above interceptor code here.. var standardOutput = new StreamWriter(Console.OpenStandardOutput()); standardOutput.AutoFlush = true; Console.SetOut(standardOutput); // Now all output starts flowing back to console