Check whether the program is started and mutex is abnormal in C #.

Background]

In a recent project, I am in charge of the client module. Requirement: when starting the client, you need to determine whether the client has been started (Singleton ). So I decided to use mutex to implement this function. The Code is as follows:

Bool initiallyowned = true; bool iscreated; mutex M = new mutex (initiallyowned, "XXXXX", out iscreated); If (! (Initiallyowned & iscreated) {common. messageex. MSG ("the client has been started! "); Return ;}

In most cases, this function can be used to determine whether the client has been started.

[New requirements]

Nnd, one day there is a need for metamorphosis (BT). After the main form of the client pops up a sub-form, the sub-form needs to be minimized, while the sub-form needs to be minimized at the same time, when the main form is restored, the sub-form is restored (I really want to say, your uncle, the operating system has never met such a Bt requirement ).

[Mutex exception]

After some hard work, we finally achieved the BT demand. Occasionally, when a subform pops up on the client, the system is minimized, and then I start a new client. I was scared at the moment ---- nnd was able to start normally.

[Solution]

Finally, after debugging the program, I found that when the client has been started and is in the process of the above operations, I can start the client again and mutex can be created. Therefore, I can only perform the following operations (Singleton ):

Int I = 0; Process [] pros = process. getprocesses (); foreach (PROCESS p in PROs) {If (P. processname. Equals ("XXXXX "))
{
++ I;
}
If (I> 1) {break ;}
}

If (I> 1)
{
Common. messageex. MSG ("the client has been started! ");
Return;
}

[Why can't mutex judge]

As for why mutex cannot be judged, I have not figured it out yet. I hope to share this blog with you !!!