Hi,
I've read "Cybertof"' s thread (04/19/04) & the article he provided in a link
about accessing UI elements from a thread that did not create them. What the
authors are saying makes plenty of sense. However, using the control's
Invoke method handles calling it's methods, but what about accessing the
control's properties from another thread? What's the proper way to do that?
--
John C. Bowman
Software Engineer
Thermo Electron Scientific Instruments Div.
<Remove this before reply> jo*********@the rmo.com 5  1417 
<"John Bowman" <<Remove this before reply> jo*********@the rmo.com>>
wrote: I've read "Cybertof"' s thread (04/19/04) & the article he provided in a link
about accessing UI elements from a thread that did not create them. What the
authors are saying makes plenty of sense. However, using the control's
Invoke method handles calling it's methods, but what about accessing the
control's properties from another thread? What's the proper way to do that?
Again, through a delegate and Invoke. You shouldn't access the property
directly from a non-UI thread.
--
Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Jon,
Thanks for the quick reply. I kind of suspected that would be the answer
<g>. However, I don't understand (code wise) how to use Invoke to access a
property. I understand how to use it for accessing a method. Do you just
treat the property of interest as if it's a method that has no arguments?
Any example code?
TIA,
John
"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote in message
news:MP******** *************** *@msnews.micros oft.com... <"John Bowman" <<Remove this before reply> jo*********@the rmo.com>>
wrote: I've read "Cybertof"' s thread (04/19/04) & the article he provided in a
link about accessing UI elements from a thread that did not create them. What
the authors are saying makes plenty of sense. However, using the control's
Invoke method handles calling it's methods, but what about accessing the
control's properties from another thread? What's the proper way to do
that?
Again, through a delegate and Invoke. You shouldn't access the property
directly from a non-UI thread.
--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
<"John Bowman" <<Remove this before reply> jo*********@the rmo.com>>
wrote: Thanks for the quick reply. I kind of suspected that would be the answer
<g>. However, I don't understand (code wise) how to use Invoke to access a
property. I understand how to use it for accessing a method. Do you just
treat the property of interest as if it's a method that has no arguments?
No - you would have to create a delegate which accessed the property,
and invoke that delegate.
Any example code?
Well, just:
delegate string StringReturning Delegate();
string GetLabelText()
{
return label.Text;
}
....
myControl.Invok e
(new StringReturning Delegate(myCont rol.GetLabelTex t());
should work.
--
Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Hi John,
You can use a method to access a property. This would be a special method
that you call thru Invoke and this method sets or gets the property. The
other way is to create a delegate to invoke the 'get' or 'set' accessor of
the property directly. Hoewever IMHO the first is more easy to use. For
invoking the accessor directly you can follow this link http://groups.google.ca/groups?hl=en...sor%2Bstoitcho
Look for my post, which is last in the thread.
--
HTH
B\rgds
Stoitcho Goutsev (100) [C# MVP]
"John Bowman jo*********@the rmo.com>" <<Remove this before reply> wrote in
message news:u2******** ******@TK2MSFTN GP09.phx.gbl... Jon,
Thanks for the quick reply. I kind of suspected that would be the answer
<g>. However, I don't understand (code wise) how to use Invoke to access a
property. I understand how to use it for accessing a method. Do you just
treat the property of interest as if it's a method that has no arguments?
Any example code?
TIA,
John
"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote in message
news:MP******** *************** *@msnews.micros oft.com... <"John Bowman" <<Remove this before reply> jo*********@the rmo.com>>
wrote: I've read "Cybertof"' s thread (04/19/04) & the article he provided in
a link about accessing UI elements from a thread that did not create them.
What the authors are saying makes plenty of sense. However, using the control's
Invoke method handles calling it's methods, but what about accessing
the control's properties from another thread? What's the proper way to do
that?
Again, through a delegate and Invoke. You shouldn't access the property
directly from a non-UI thread.
--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Jon & Stoitcho,
Thanks for the help. I should be able to continue from here.
John
"Stoitcho Goutsev (100) [C# MVP]" <10*@100.com> wrote in message
news:ux******** ******@tk2msftn gp13.phx.gbl... Hi John,
You can use a method to access a property. This would be a special method
that you call thru Invoke and this method sets or gets the property. The
other way is to create a delegate to invoke the 'get' or 'set' accessor of
the property directly. Hoewever IMHO the first is more easy to use. For
invoking the accessor directly you can follow this link
http://groups.google.ca/groups?hl=en...sor%2Bstoitcho Look for my post, which is last in the thread.
--
HTH
B\rgds
Stoitcho Goutsev (100) [C# MVP]
"John Bowman jo*********@the rmo.com>" <<Remove this before reply> wrote in
message news:u2******** ******@TK2MSFTN GP09.phx.gbl... Jon,
Thanks for the quick reply. I kind of suspected that would be the answer
<g>. However, I don't understand (code wise) how to use Invoke to access
a property. I understand how to use it for accessing a method. Do you just
treat the property of interest as if it's a method that has no
arguments? Any example code?
TIA,
John
"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote in message
news:MP******** *************** *@msnews.micros oft.com... <"John Bowman" <<Remove this before reply> jo*********@the rmo.com>>
wrote:
> I've read "Cybertof"' s thread (04/19/04) & the article he provided
in a link > about accessing UI elements from a thread that did not create them. What the > authors are saying makes plenty of sense. However, using the
control's > Invoke method handles calling it's methods, but what about accessing
the > control's properties from another thread? What's the proper way to
do that?
Again, through a delegate and Invoke. You shouldn't access the
property directly from a non-UI thread.
--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
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