Press ALT+TAB programatically

Question

Hello members
I am working on a program in which i called  a program exe file but the program which i called, using system.diagnostic.start ,givse output
when "alt+tab" is pressed is pressed
followed by "tab"
and finally "Enter"
i dont want any user input in middle i want automatically output from the program plz guide how i can press space bar programatically.
I used the following codes to do this
if (e.Result.Text == "Time" )     // TIME has been added to sppech grammmer first
{
Process .Start( "C://Program Files//amitbot.exe" );
Thread .Sleep(200);
SendKeys .Send( "%{TAB}" );
Thread .Sleep(200);
SendKeys .Send( "{TAB}" );
Thread .Sleep(200);
SendKeys .Send( "{ENTER}" );
}
While this code successfully executes the ALT+TAB command, But the following commands are not executed. Instead message is displayed that programme can't be changed while debugging.
plz give a detailed answer i am struck very badly.

Vulpes · Answer

Is the process which receives the keys running in debug mode?
If it is, then try running it without a debugger attached.

Amit Ranjan · Answer

After adding Process.WaitForInputIdle, I dont get the error message that I got before  'Program cant be changed while debugging'. But the problem still persists, it takes the first command (ALT+ TAB) and misses out all the subsequent sendkey commands.

Sam Hobbs · Answer

The message "programme can't be changed while debugging" indicates to me that you have not exited the program doing the SendKeys before you change the source code and try doing another test. If that is what is happening then the additional test(s) are trying to do a build but it (they) cannot complete the build while the previous execution is still executing.
Also, note that many developers use SendKeys and many developers do not. SendKeys sounds easy and obvious but there is probably an easier way to do it; you just need to know a little bit more about how Windows works.

Vulpes · Answer

It may be a synchronization problem.
If the process has a message loop (i.e. it's a Windows Forms or WPF application), I'd try calling Process.WaitForInputIdle before sending each key to make sure it's in a position to respond:
if (e.Result.Text == "Time")     // TIME has been added to sppech grammmer first
{
Process p = Process.Start("C://Program Files//amitbot.exe");
Thread.Sleep(200);
p.WaitForInputIdle();
SendKeys.Send("%{TAB}");
Thread.Sleep(200);
p.WaitForInputIdle();
SendKeys.Send("{TAB}");
Thread.Sleep(200);
p.WaitForInputIdle();
SendKeys.Send("{ENTER}");
}