Thread.IsAlive and Thread.ThreadState==ThreadState.Running

Question

I am using to check the condition of a thread with if(Thread.IsAlive). A form is running in this thread. At times during execution, even though the form remains open, the call to Thread.IsAlive seems to be evaluating to false. I thought to perform the same check with if(Thread.ThreadState==ThreadState.Running). Is it the right way to do? If not, what is the possible work around?

Mauriac

@daveL : even i hate it when i say it seems to behave like this. But the problem is that I can see the form that is running on that thread on my desktop, yet thread.isalive code is not getting executed. – Mauriac

Seems like @daveL has a hard time dealing with ambiguity, at least it seems that way... :p – Rachellerachis

Answer 1

msdn Thread.IsAlive Property true if this thread has been started and has not terminated normally or aborted; otherwise, false.

msdn Thread.ThreadState

• Running
  The thread has been started, it is not blocked, and there is no pending ThreadAbortException.
• StopRequested
• SuspendRequested
• Background
• Unstarted
• WaitSleepJoin
• Suspended
• AbortRequested

I think now it's clear Running is not the same as IsAlive

Ambur

IsAlive is mostly useful when you're starting a thread. if(!thread.IsAlive) thread.Start(); It's not a safe way to see if a thread is RUNNING because there are many states between NOT STARTED and STARTED that aren't equal to RUNNING. IsAlive really just tells you not to try to start it again. – Rachellerachis

Is it a safe way to periodically check to make sure the thread has not exited ? – Toddtoddie

Suspended no longer appears to be a valid threadstate. Can anyone recommend an alternative? – Unification