when u press left click and move mouse, what event be happend if stop moving?

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hi. i want to design the paint software. when press left click and move mouse, what event happen if stop move and left click be pressed too.please guide me.thanks

Posted 26-Nov-12 18:20pm

Leila Mansouri

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[no name] 27-Nov-12 0:21am

Not clear..

Leila Mansouri 27-Nov-12 0:37am

when i press left bottom of mouse, MouseDown event be called.
after this if i move mouse, MouseMove event be called.
after this, if i stop move, what event be called?

[no name] 27-Nov-12 0:38am

On which control you are firing these events...??

Leila Mansouri 27-Nov-12 1:00am

i want to draw paint in a user control. for this user control, i need event.

Sergey Alexandrovich Kryukov 27-Nov-12 0:45am

No, event is not "called", because this is not a method. Even is invoked, and then all the event handlers are called, according to the invocation list found in the event instance. And, of course...
--SA

Vani Kulkarni 27-Nov-12 0:29am

Your question is unclear. Please elaborate.

Sergey Alexandrovich Kryukov 27-Nov-12 1:01am

Quite clear, I think. It's just hard to follow the logic (or, rather, the absence of logic). So, I answered, please see.
--SA

Leila Mansouri 27-Nov-12 1:57am

thanks --SA

[no name] 27-Nov-12 0:49am

Yes, SA is right.. Events are custom delegates.. You can't invoke them..

Sergey Alexandrovich Kryukov 27-Nov-12 0:59am

They are not custom delegates. An event can be invoked, but only in the code of the declaring class, nowhere else, not even in a derived class. Events instances are much like delegate instanced, with some severe limitations (I just mentioned one); and those limitations are what makes the events so valuable. In principle, all the software could work without events with delegate instances instead of them. Events just add to safety.

I decided to answer, please see.
--SA

[no name] 27-Nov-12 1:01am

Nope, they are custom delegates..

Sergey Alexandrovich Kryukov 27-Nov-12 1:06am

Well, could you explain it? And not on some phrase you have read from some article -- it could be inaccurate. From facts.
--SA

[no name] 27-Nov-12 1:10am

http://msdn.microsoft.com/en-us/library/ms366768.aspx

Sergey Alexandrovich Kryukov 27-Nov-12 1:23am

You totally miss the point of all of it. There is no such statement in this article.
This is something important to understand. They call two very difference entities by the word "delegate". One is delegate type. Another is delegate instance. Now -- probably shocking fact for your! -- a delegate instance's type is NOT any delegate type. Instead, this is some class. Call GetType and you will see. Same thing is about the event instance. This is a certain deviation from the usual declaration type-instance.

Not very simple things, conceptually, and MSDN does not really explain it.
--SA

Leila Mansouri 27-Nov-12 1:16am

thanks Krunal R

Leila Mansouri 27-Nov-12 1:15am

thanks --SA

Sergey Alexandrovich Kryukov 27-Nov-12 1:19am

You are welcome. If you got it, please consider accepting my answer formally (green button) -- thanks.
--SA

Leila Mansouri 27-Nov-12 1:58am

Thanks Krunal R

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Sergey Alexandrovich Kryukov · Accepted Answer · 2012-11-26T18:55:00

Please see my comment to the question.

...and of course, there is no any event corresponding to the "stop" of the motion; and such event cannot exist in principle. By a very, very simple reason: mouse events are generated by a hardware driver, and there is no a hardware interrupt related to "stop" of the motion, and such interrupt cannot exist. And, in turn, this is so by a very, very simple reason: there cannot be a "good" criterion for such an event. This is just the lack of events for certain period of time.

Not just thinking that such even can exist, but the very desire of such facility is a huge misconception. Even if you had something similar, it would be really unusable. In principle, you could simulate something resembling such behavior using a timer. You could create an event invoked (please see my comment to the question again) by the timer event handler in case of absence of mouse even for certain period of time, if some mouse button is pressed. And now, imagine the nightmare the user would experience...

—SA