In a C# .NET GUI Application. I also need the console in the background for some tasks. Basically, I'm using a Thrid Party library for some processing (takes lot of time) which writes its intermediate results to console. This processing is a computationally time taking task. So, I'm assigning this task to backgroundworker. I mean background worker calls these library functions. But problem is there is no way for me to show the user status of computation, because I don't have source of the library. I was hoping Console will be shown. But surprisingly Console.WriteLine
doesn't seem to work. I mean, there isn't any console window shown. How come?
EDIT:
I tried setting application type = console. But there seems to be a problem. Only, main thread is able to access th开发者_开发百科e console. Only Console.WriteLine
s executed by main (Application) thread are displayed on console. Console.WriteLine
s executed by other (BackgroundWorker)threads of the GUI, the output is not shown. I need console only for Background workers. I mean, When background worker starts, console starts & when it ends console will be off.
Create your own console window and use the Console.SetOut(myTextWriter); method to read anything written to the console.
Set your application type to "Console Application". Console applications can also create GUI windows with no problem, and write to the console at the same time.
If you don't have control of the main application, and you want to make sure that a console is shown, you can p/invoke AllocConsole
(signature here).
This isn't the same as being a console application though, your application will always get a separate console window, which might be surprising to someone who launched it from a command prompt window. You can work around that with AttachConsole
(signature and example here) but shell redirection of the output still won't work. That's why I suggest setting the application subsystem to console if you can.
Followed by @jgauffin, here is the implementation of Console.SetOut
method.
Create a TextWriter
inherited class.
using System;
using System.Text;
using System.IO;
using System.Windows.Forms;
namespace ConsoleRedirection
{
public class TextBoxStreamWriter : TextWriter
{
TextBox _output = null;
public TextBoxStreamWriter(TextBox output)
{
_output = output;
}
public override void Write(char value)
{
base.Write(value);
_output.AppendText(value.ToString()); // When character data is written, append it to the text box.
}
public override Encoding Encoding
{
get { return System.Text.Encoding.UTF8; }
}
}
}
And in the Form, code as below.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;
namespace ConsoleRedirection
{
public partial class FormConsole : Form
{
// That's our custom TextWriter class
TextWriter _writer = null;
public FormConsole()
{
InitializeComponent();
}
private void FormConsole_Load(object sender, EventArgs e)
{
// Instantiate the writer
_writer = new TextBoxStreamWriter(txtConsole);
// Redirect the out Console stream
Console.SetOut(_writer);
Console.WriteLine("Now redirecting output to the text box");
}
// This is called when the "Say Hello" button is clicked
private void txtSayHello_Click(object sender, EventArgs e)
{
// Writing to the Console now causes the text to be displayed in the text box.
Console.WriteLine("Hello world");
}
}
}
Original code is from https://saezndaree.wordpress.com/2009/03/29/how-to-redirect-the-consoles-output-to-a-textbox-in-c/ You can check the link for cross-thread calls and advanced implementations at comments.
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