.NET: Copy Console Output to a Log File

The following ConsoleLogger class makes it easy to copy all of the Console output to a log file.

ConsoleLogger class usage:

public class Program
{
	static void Main(string[] args)
	{
		string logFile = "application.log";
		using (var consoleLogger = new ConsoleLogger(logFile))
		{
			Console.WriteLine("Hello, World!");

			// NOTE: Even logs data input by the user
			Console.ReadLine();

		 	// NOTE: Put entire application inside this block
		}
	}
}

ConsoleLogger class:

public class ConsoleLogger : IDisposable
{
	private FileStream fileStream;
	private StreamWriter fileWriter;
	private TextWriter originalConsoleOut;

	internal class MultiTextWriter : TextWriter
	{
		private IEnumerable<TextWriter> writers;

		public MultiTextWriter(IEnumerable<TextWriter> writers)
		{
			this.writers = writers;
		}

		public override void Write(char value)
		{
			foreach (var writer in writers)
				writer.Write(value);
		}

		public override void Write(string? value)
		{
			foreach (var writer in writers)
				writer.Write(value ?? string.Empty);
		}

		public override void Flush()
		{
			foreach (var writer in writers)
				writer.Flush();
		}

		public override Encoding Encoding
		{
			get { return Encoding.UTF8; }
		}
	}

	public ConsoleLogger(string logPath)
	{
		// NOTE: Store the original console output
		originalConsoleOut = Console.Out;

		// NOTE: Create log file
		fileStream = new FileStream(logPath, FileMode.Create, FileAccess.Write, FileShare.Read);
		fileWriter = new StreamWriter(fileStream);
		fileWriter.AutoFlush = true;

		// NOTE: Redirect console output to both console and file
		Console.SetOut(new MultiTextWriter(new TextWriter[] { originalConsoleOut, fileWriter }));
	}

	public void Dispose()
	{
		Console.SetOut(originalConsoleOut);
		if (fileWriter != null)
		{
			fileWriter.Dispose();
		}
		if (fileStream != null)
		{
			fileStream.Dispose();
		}
	}

}

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