Event preemption

[James]

Hi all,

I am seeing some unexpected behaviour in a single threaded winforms app
and was hoping someone could explain what is going on.
I have two events attached to a chart control on my form, and during
execution one event seems to preempt the execution of the other.

My code looks similar to the following:

private void MyChart_Click(object sender, System.EventArgs e)
{
....do some logic tests
GetSomeData();
}

// This event is attached to the context menu for the chart control.
private void DrillDownMenuItem_Click(object sender, System.EventArgs e)
{
....do stuff
}

private DataSet GetSomeData()
{
....setup tasks
....Call web service
....finish stuff
}

What happens is that when I right click and select drill down from the
chart controls context menu the MyChart_Click event fires and does the
logic tests. Execution then steps into the GetSomeData method, but when
the web service is called execution jumps to the
DrillDownMenuItem_Click event. This runs to completion then execution
returns to the GetSomeData method which finishes and finally returns to
the MyChart_Click event handler.
Can someone explain why this is so?

Thanks very much,
James

[Jon Skeet [C# MVP]]

James <no**********@mailinator.com> wrote:

I am seeing some unexpected behaviour in a single threaded winforms app
and was hoping someone could explain what is going on.
I have two events attached to a chart control on my form, and during
execution one event seems to preempt the execution of the other.

My code looks similar to the following:

Rather than similar code, could you post a short but complete program
which demonstrates the problem?

See http://www.pobox.com/~skeet/csharp/complete.html for details of
what I mean by that.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[James]

Hi Jon,

Thanks very much for your reply.

I have figured out the problem myself now. It turns out it is a bug in
the third party control I am using. I am making the vendor aware of the
problem now.
Nice posting guidelines by the way ;-)

Regards,
James Fitzsimons