C# Discussion Boards - CodeProject

User 665823-Jul-03 1:16

23-Jul-03 1:16

Maybe it's only about 5% of the .NET Framework, but unfortunately a very essential one if you want to write GUI applications Frown | :(

modified 12-Sep-18 21:01pm.

Is there a clean way to remove a control and it's associated event handlers?

work_to_live22-Jul-03 5:36

work_to_live

22-Jul-03 5:36

I haven't found a clean way to remove a control (say a button) and any associated event handlers. What I do now is delete the control from the form, then find the event handlers in the code, and delete them. When I recompile, I get errors due to the deleted event handler code, and have to perform more surgery to clean them up. I'm new to dotNet, so be kind...

There must be an easier way!

Re: Is there a clean way to remove a control and it's associated event handlers?

Frank Olorin Rizzi22-Jul-03 7:17

Frank Olorin Rizzi

22-Jul-03 7:17

If you're talking at design time,
then I have run into the same "problem"...
removing a control from the design view removes the declaration and instanciation of that control from the IDE-generated code but not anything related like the even handlers..
..I usually do that by hand.

If you're talking at run time, I think that removing the control from the Controls collection of the form should do the trick (the handlers are still in the compiled code but they will not get called...)

HTH,
Olorin

Re: Is there a clean way to remove a control and it's associated event handlers?

work_to_live22-Jul-03 9:27

work_to_live

22-Jul-03 9:27

Sorry, I was referencing design time. The functionality you reference is what I have seen. It just seems odd that you can't delete the event handlers in one fell swoop.

Oh well.

Thanks for your reply.

Re: Is there a clean way to remove a control and it's associated event handlers?

James T. Johnson22-Jul-03 8:13

James T. Johnson

22-Jul-03 8:13

Any handlers added by using the IDE will get removed when you delete the control. If you add handlers by hand then you'll have to remove them by hand as well.

James

"I despise the city and much prefer being where a traffic jam means a line-up at McDonald's"
Me when telling a friend why I wouldn't want to live with him

Re: Is there a clean way to remove a control and it's associated event handlers?

work_to_live22-Jul-03 9:29

work_to_live

22-Jul-03 9:29

What I see is the declaration and instantiation of a control (say a button) is removed when you delete the button, but not any associated event handlers, not even those created with the IDE.

Re: Is there a clean way to remove a control and it's associated event handlers?

Ista22-Jul-03 9:22

Ista

22-Jul-03 9:22

You can also create a macro to do that for you

passing this as read/write

Ista22-Jul-03 5:29

Ista

22-Jul-03 5:29

I need to pass a reference to my object

CEmployee
...
CallMyMethod(ref this);

but that doesnt work becuase this is read only.

how would a gain a writable reference to it?

nick

Dont look at me funny for asking this

RB@Emphasys22-Jul-03 4:32

RB@Emphasys

22-Jul-03 4:32

Alright ladies and gools,

I've got a rather serious question. Does anyone know of any source code sitting around for pdf417 barcode encoding? I've seen some examples out there in c, and maybe one in Java, but I was hoping I might find one in c#.

Thanks in advance for the help,
Ryan

Re: Dont look at me funny for asking this

Ista22-Jul-03 9:23

Ista

22-Jul-03 9:23

let me have the com you are using and I'll make it for you.

remoting.config question

LongRange.Shooter22-Jul-03 4:11

LongRange.Shooter

22-Jul-03 4:11

I read through the remoting tutorial and the examples they gave were not clear enough. Can anyone tell me if I am setting this up correctly?

I have a class library named RemotingObjectAccess.dll
In the class library are 5 classes that inherit MarshalByRefObject:
myNamespace.PageManager
myNamespace.RuleManager
myNamespace.EventManager
myNamespace.HeaderManager
myNamespace.QuestionManager

If I understand the tutorial correctly:
I run my web in a virtual directory. DONE
I put my DLL and it's dependancies in the bin directory of the web. DONE
I create a remoting.config file and put it in the root of the virtual server. DONE

This is what I have the question on.
I couldn't get the XML to be visible in the post so....assume the XML is correct.

I set the application to my class library name:

application name=RemotingObjectAccess

Under services I defined each class within the library and set the URI to the 'class library name'.SOAP :

wellknown mode="Singleton" type="myNamespace.PageManager" objectUri="RemotingObjectAccess.soap
wellknown mode="Singleton" type="myNamespace.QuestionManager" objectURI="RemotingObjectAccess.soap

etc.
and I defined the channel to use the HTTP channel, port 80.

That is my understanding of how I should map my DLL name and individual class names into the various entries in the remoting.config file. Did I understand this correctly???

The documentation also says that the library would not be loaded until the first transaction hits the server. How can I guarantee I get a transaction into the server before I attempt to remotely connect to these classes? Since these are development servers, my remote connection could well be the first transaction!!!

Thanks for any help and input.

_____________________________________________
_{The world is a dangerous place.
Not because of those that do evil,
but because of those who look on and do nothing.}

probs with print: Generic/Text only :confused:

troels_sorensen22-Jul-03 4:09

troels_sorensen

22-Jul-03 4:09

Hi.

I'm trying to send text to a Epson TM-T88II Reciept printer. the printer is installed as a system printer on win XP.

I've got some drivers from their homepage wich i got to work. the performance however is not acceptable (~30 sec for 20 centimeters).

I tried printing a windows testpage with the MS Generic/Text Only driver. this took ~1 (one!) second for 30 centimeters. So i naturally want to use this driver.
BUT (there is always a 'but'...) When i try to print in my program i get this error:
"The data area passed to a system call is too small".

this is kind of strange since the program has not reacht my printpage event yet....
The program generates the error in system.drawing.printing.OnStartPrint (or something like that) which has nothing to do with anything.. :-/

i've i try a different driver I do not get this error.
I've looked a bit around the web and seen others with similar probs but no solution.
Can anyone help me?!!

here's my code:

---------------------------------
public void PrintBon()
{
try
{
//for text
m_printBon = new PrintDocument();
m_printBon.PrintPage += new PrintPageEventHandler
(this.printBon_PrintBon); <--- Error occurs here. before the program goes to my PrintBon event.

m_printBon.Print();

}
catch(Exception ex)
{
throw ex;
}
}

private void printBon_PrintBon(Object sender, PrintPageEventArgs ev)
{
ev.Graphics.DrawImage(logo, 80, 0, 130, 50);

ev.Graphics.DrawString(m_printString, m_printFont, Brushes.Black, 0, 60);
ev.HasMorePages = false;
}
----------------------

Re: probs with print: Generic/Text only :confused:

troels_sorensen22-Jul-03 23:52

troels_sorensen

22-Jul-03 23:52

apparently .NET only sends Graphics to a printer. therefore the Generic/text only driver cant accept the input.
I found a tutorial on how to send raw data to a printer.

http://support.microsoft.com/default.aspx?scid=kb;EN-US;322091

OMG | :OMG:

Call an unknown object

Ista22-Jul-03 3:57

Ista

22-Jul-03 3:57

I want to call a method clear on an object. I know it has the clear method but I dont what class it is

do i use method info class?

Re: Call an unknown object

David Stone22-Jul-03 4:39

David Stone

22-Jul-03 4:39

You could use Reflection and the MethodInfo type, however, are you sure that the object doesn't implement an interface that has the Clear method? In that case, you could cast the object to the interface and then call the method based on the interface. Otherwise, how do you know the object implements Clear()?

Hawaian shirts and shorts work too in Summer.
People assume you're either a complete nut (in which case not a worthy target) or so damn good you don't need to worry about camouflage...
-Anna-Jayne Metcalfe on Paintballing

Re: Call an unknown object

Ista22-Jul-03 8:15

Ista

22-Jul-03 8:15

Well I created the class and they all have base classes. I could create a default interface but I didn't really feel like doing it.

Re: Call an unknown object

David Stone22-Jul-03 10:23

David Stone

22-Jul-03 10:23

Then you could cast the object to the base class before calling the method. That should work, and it'll also give you intellisense in VS.NET.

C++ to C#

zoltan_ie22-Jul-03 0:43

zoltan_ie

22-Jul-03 0:43

int done;

....

if(done)
break;

It been a long time since i've done C++ but what is the correct statement in C#?

???
if(1 == done)
break;

if(0 != done)
break;

???

Re: C++ to C#

Mazdak22-Jul-03 0:53

Mazdak

22-Jul-03 0:53

C# and C++ have the same syntax. You can use it in C# too.

if(done)
break;

is correct for both.

Mazy

No sig. available now.

Re: C++ to C#

zoltan_ie22-Jul-03 0:56

zoltan_ie

22-Jul-03 0:56

Visual Studio .NET considers the code to be an error:

Cannot implicitly convert type 'int' to 'bool'

Re: C++ to C#

Mazdak22-Jul-03 1:23

Mazdak

22-Jul-03 1:23

You didn't say it returns int value. Cast it too bool.

if((bool)done)
...

Mazy

No sig. available now.

Re: C++ to C#

zoltan_ie22-Jul-03 1:40

zoltan_ie

22-Jul-03 1:40

well the casting still throws up the same error
Cannot convert type 'int' to 'bool'

any hoo.

what number does done have to be for it to satisfy the condition?

Re: C++ to C#

Mazdak22-Jul-03 1:46

Mazdak

22-Jul-03 1:46

So use If(done==1) .It returns error too?

Mazy

No sig. available now.

Re: C++ to C#

Ista22-Jul-03 3:56

Ista

22-Jul-03 3:56

more like while(true)
break;

its not a full int world anymore

Re: C++ to C#

Meysam Mahfouzi22-Jul-03 1:46

Meysam Mahfouzi

22-Jul-03 1:46

zoltan_ie wrote:
It been a long time since i've done C++ but what is the correct statement in C#?

???
if(1 == done)
break;

if(0 != done)
break;

???

Use above lines, no problem

Don't forget, that's

Persian Gulf

not Arabian gulf!

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