Redirecting Console.WriteLine() to Textbox

I'm building this application in Visual Studio 2010 using C#.

Basically there are 2 files, form1.cs (which is the windows form) and program.cs (where all the logic lies).

//form1.cs public partial class Form1 : Form { //runButton_click function } //program.cs class Program { static void Main() { while(blah-condition) { //some calculation Console.WriteLine("Progress " + percent + "% completed."); } } }

There is a Run button and a blank textbox.

When the user hits the Run button, program.cs will perform some task and constantly printing out the progress using Console.WriteLine() onto the console (command prompt).

Question: How can I print to the textbox on form1 instead of printing into command prompt? I will need to print the progress constantly without any user action.

Thanks in advance!

By the way, it doesn't have to be a textbox, it can be a label or something else that can take text. I chose textbox because it makes more sense to me.

Start by creating a new TextWriter that is capable of writing to a textbox. It only needs to override the Write method that accepts a char, but that would be ungodly inefficient, so it's better to overwrite at least the method with a string.

public class ControlWriter : TextWriter { private Control textbox; public ControlWriter(Control textbox) { this.textbox = textbox; } public override void Write(char value) { textbox.Text += value; } public override void Write(string value) { textbox.Text += value; } public override Encoding Encoding { get { return Encoding.ASCII; } } }

In this case I've had it just accept a Control, which could be a Textbox, a Label, or whatever. If you want to change it to just a Label that would be fine.

Then just set the console output to a new instance of this writer, pointing to some textbox or label:

Console.SetOut(new ControlWriter(textbox1));

If you want the output to be written to the console as well as to the textbox we can use this class to create a writer that will write to several writers:

public class MultiTextWriter : TextWriter { private IEnumerable<TextWriter> writers; public MultiTextWriter(IEnumerable<TextWriter> writers) { this.writers = writers.ToList(); } public MultiTextWriter(params 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); } public override void Flush() { foreach (var writer in writers) writer.Flush(); } public override void Close() { foreach (var writer in writers) writer.Close(); } public override Encoding Encoding { get { return Encoding.ASCII; } } }

Then using this we can do:

Console.SetOut(new MultiTextWriter(new ControlWriter(textbox1), Console.Out));