Help please , how to reach other program control.

using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace ConsoleApplication1
{
    class Program
    {
        // For Windows Mobile, replace user32.dll with coredll.dll
        [DllImport("user32.dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool SetForegroundWindow(IntPtr hWnd);


        static void Main(string[] args)
        {
            Process myProcess = Process.Start(@"c:\windows\notepad.exe");
            SetForegroundWindow(myProcess.Handle);
            if (myProcess.Responding)
                SendKeys.SendWait("This text was entered using the System.Windows.Form=s.SendKeys method.");
            Console.ReadLine();
        }
    }
}

I don't know how to code this, but I would investigate doing it in the following manner:
When Button(2) is pressed, App(2) should send a message to App(1). When App(1) receives this message, it should get the text from Textbox(1), then compose a message that includes the text as a parameter and then sends that message to App(2). App(2) then processes the message and parameter and displays the text in Textbox(2). :)

If you can have code in the application with the first textbox that can send information on a channel, then catch that broadcast in the second application, you can use wcf. Check out this article:

.NET Interprocess Communication Revisited[^]

It has the code to easily implement interprocess communication.

As an simple alternative use remoting. This allows you to call a method on an other process. Helmut Güldenagel his .NET Remoting Sample[^] on codeproject, is probably a good starting point.

Regards
Piet

Finally ... I tried to get the handle of utorrent control "Edit"(textbox)
And I succeded but now , How to use the handle to get text from the control "Edit" >>> This is the Problem for now.
----------------------------------------------------------------------------

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices ;
using System.Diagnostics;

namespace WindowsFormsApplication5

{
    public partial class Form1 : Form
    {
        //load FindWindow method
        [DllImport("user32.dll", SetLastError = true)]
        static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
        //load FindWindowEx method
        [DllImport("user32.dll", SetLastError = true)]
        static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string lpszClass, string lpszWindow);

public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{

IntPtr Program = new IntPtr(0);
IntPtr myControl = new IntPtr(0);

Program = FindWindow("µTorrent4823DF041B09", null);
if (Program.Equals(IntPtr.Zero))
label1.Text=("Notepad Not Running");
else
{


myControl = FindWindowEx(Program, IntPtr.Zero, "Edit", null);
if (myControl.Equals(IntPtr.Zero))
{
label1.Text = "µTorrent doesn't have an Edit component ?";
}
else
{
label1.Text = "Edit Control: " + myControl.ToString();

}

Controlling one program by another is always a bad idea, especially if one program is not designed to be controlled (remoting, WPF, sockets, other IPC). The is abuse and going against OS paradigm designed to isolate processes. Right approach is the component approach; the components should be put together and integrated in one process, not different processes. You have enough flexibility in programming technologies. You are just started to move in wrong direction. Don't do it until it's too late.

—SA