Re: Memory leaks - C# Discussion Boards

Re: A Comprehensive Logging Package for .NET

Heath Stewart28-Jul-04 6:39

28-Jul-04 6:39

If you have specific problems with an application/library, you should ask the authors and/or their support contacts. Since NSpring is hosted on SourceForge, there are a couple differnet forums you can use.

If you have questions specific to C#, this is the place to ask.

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Re: A Comprehensive Logging Package for .NET

pat27088128-Jul-04 6:53

pat270881

28-Jul-04 6:53

hello,

oh i thought i can post it here because the framework is also explained on this site. on the www.SourceForge.net page i didn't find a forum where i can post my question?? Frown | :(

yours sincerely

patrick

Re: A Comprehensive Logging Package for .NET

Heath Stewart28-Jul-04 6:59

Heath Stewart

28-Jul-04 6:59

No, the ".NET Framework" is discussed on this site, not the "NSpring Framework". Specifically, this forum is for discussions about C#, one of many languages that target the CLR (part of the .NET Framework).

If there is an article you found on this site that discusses NSpring, then you should ask this question on that articles message board at the bottom of the page; that's what it's there for.

If you go to the SourceForge project page and look, you'll see a Support[^] link.

Microsoft MVP, Visual C#
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Re: A Comprehensive Logging Package for .NET

Giles28-Jul-04 21:00

Giles

28-Jul-04 21:00

Perhaps posting your question on the article, Jeff may respond.

"Je pense, donc je mange." - Rene Descartes 1689 - Just before his mother put his tea on the table.

Shameless Plug - Distributed Database Transactions in .NET using COM+

Re: A Comprehensive Logging Package for .NET

pat27088128-Jul-04 22:26

pat270881

28-Jul-04 22:26

hello,

i already post my question on the forum of jeff, but he did not answer. Sigh | :sigh:

yours sincerely

patrick

Memory leaks

blankg28-Jul-04 5:37

blankg

28-Jul-04 5:37

i am using a lot of bitmap objects in my application , when i get to over a 100 objects with bitmaps my application slows and eventualy crashes, how can i handle the memory problem ? is there a better way to save images than with bitmaps?

Re: Memory leaks

Nick Parker28-Jul-04 6:27

Nick Parker

28-Jul-04 6:27

blankg wrote:
is there a better way to save images than with bitmaps?

When you are done with the Bitmap call Dispose(). Another option is to use the C# using keyword so that appropriate try/finally blocks are emmited and then your Bitmap object will be cast to an IDisposable and Dispose() will be called automagically for you.

using (Bitmap b = new Bitmap("C:\..."))
{
// use b here
}

- Nick Parker
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Re: Memory leaks

Heath Stewart28-Jul-04 6:37

Heath Stewart

28-Jul-04 6:37

For any object that implements IDisposable, you should always dispose of the object when finished. This includes (and definitely is not limited to) Bitmap and Graphics. In C#, you can use the using statement to make sure that objects are disposed even in case an exception is thrown:

using (Bitmap bmp = new Bitmap(32, 32))
{
  using (Graphics g = Graphics.FromImage(bmp))
  {
    // Draw on the bitmap
  } // g.Dispose() gets called no matter what
  bmp.Save(...); // Save the bitmap
} // bmp.Dispose() gets called no matter what

This ensures that unmanaged resource (resources that aren't managed by the CLR, like native handles) are freed and that managed objects are disposed of immediately instead of the next time the GC (garbage collector) is run by the CLR.

On a note, if you call Environment.Exit finalizers (like destructors in C++...sort of) are executed but IDisposable.Dispose is not. This really isn't too important since Environment.Exit will unload the CLR and exit the host process - the OS will free all handles in use at this time. If any exceptions are thrown or you return execution to the caller, using the using statement will still dispose the object. The following is equivalent:

using (Bitmap bmp = new Bitmap(32, 32))
{
  // Use 'bmp'
}
// EQUALS
Bitmap bmp = new Bitmap(32, 32);
try
{
  // Use 'bmp'
}
finally
{
  bmp.Dispose();
}

Microsoft MVP, Visual C#
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IL code generation on the fly

SOCM_FP_CPP28-Jul-04 2:15

SOCM_FP_CPP

28-Jul-04 2:15

hi all ,
As part of my preparation for an upcoming presentation on .NET reflection API
at the next Cochin .NET user group meeting , i have created a small four function
calculator [ + , - , / , * , ( . ) , unary + , unary - , numbers ] which can evaluate
arbitary mathematical expressions.

Aim of the code is just to show how one can use Reflection.Emit code to
create an assembly on the fly.

u may download a zipped PDF file from the following url

http://www.praseedpai.com/Misc/misc.html

I hope this will give an overview to a novice developer on IL code generation

Here is how u can use the code
----------------------------------------
Copy the contents of the PDF document on to a text file ( Expr.cs ).

use C# command line compiler csc to compile the code as follows

csc Expr.cs

u may execute the program like this

Expr "2*3"

Expr "-2+3*4"

Praseed Pai

P.S :- All the numbers are treated as doubles . No decimal points are allowed in
numbers .

Re: IL code generation on the fly

Nick Parker28-Jul-04 3:12

Nick Parker

28-Jul-04 3:12

I would suggest that you write up an article covering the material in your presentation. There are too many questions that get asked in this forum, your thread will quickly disappear. Smile | :)

- Nick Parker
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Toolbox Visibility Question - Custom Controls

ddelapasse28-Jul-04 1:39

ddelapasse

28-Jul-04 1:39

Hi,

I've designed 2 custom controls (ColorButton & ColorRadioButton) that subclass off the original windows controls, but are composed of 3 images each (left cap, right cap, center slice). I need to build a set of subclasses of these buttons (ie OrangeButton,
GreenButton,...) which are identical to the parent except the bitmaps (which I have set up as properties) would be distinct. This works fine, but I don't want my base classes (ie ColorButton) to be visible in the Design view (from the toolbox). I tried making the base class protected, but that won't compile. How can I restrict one class in a dll from the toolbox while allowing the derived classes to show up?

thanks!
Deanna

Re: Toolbox Visibility Question - Custom Controls

leppie28-Jul-04 3:13

leppie

28-Jul-04 3:13

there is an attribute you can apply to your components that will prevent it from being able to show and select into the toolbox, what it is called i cannot remember look in system.componentmold.design perhaps.

^{top secret xacc-ide 0.0.1}

Re: Toolbox Visibility Question - Custom Controls

Heath Stewart28-Jul-04 4:54

Heath Stewart

28-Jul-04 4:54

Actually, there are a few and they are in the System.ComponentModel namespace.

Those are BrowsableAttribute, EditorBrowsableAttribute, DesignTimeVisibleAttribute, and DesignerSerializationAttribute (a little less like the others, but can hide the code from the code serializer).

I'm not sure if these will help, though. Customizing the toolbox in VS.NET reflects the .NET assembly you opened and looks for Control derivatives. Whether or not that code makes use of the attributes mentioned above is questionable (only giving it a try would determine such behavior).

Another attribute that may work (though I've never used it) is the ToolboxItemFilterAttribute. This would at least make the toolbox item hidden if the filter string was specified to never match anything. I doubt this would prevent the control from showing up in the toolbox customization dialog, though.

Microsoft MVP, Visual C#
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Re: Toolbox Visibility Question - Custom Controls

Nick Parker28-Jul-04 4:53

Nick Parker

28-Jul-04 4:53

Take a look at the ToolboxItemFilterAttribute[^], also, reading about the IToolboxService[^] interface and the ToolboxItem[^] class will be helpful.

- Nick Parker
My Blog | My Articles

howto generalise compareoperations?

Stephan Wright28-Jul-04 1:34

Stephan Wright

28-Jul-04 1:34

Hy everyone!

I do want to generalize some comparestatements or assignstatments in my C# proggy. I managed to do so when I had a sender object (casting it) but now there is none and I am stuck.

My datastructure looks like this:
ldata contains the data
this looks like this
ldata[]
||=> keys[]
|| ||=> keyID //id of the field to display the data in
|| ||=> telnumber //the data to being displayed
||=> telefonID //the telefonnumber for which to display data

the telefonID should not matter, you can switch the numbers but only one of those is displayed at once, meaning you select one and the data for this number is displayed. But this doesn't matter concering my problem because at this stage the number has already been selected and I do just have to display the data for the selected number or check for changes before either switching numbers or just to save them.

My code looks like this at the moment:

//displaying the data<br />
for(li=0;li<ldata[0].keys.Length;li++)<br />
{<br />
  if(ldata[0].keys[li].keyId==1)<br />
  {<br />
    txtNameKey01.Text=ldata[0].keys[li].telephoneNo;<br />
  }<br />
  // repeated for all 12 TextBoxes <br />
}<br />
<br />
// comparing for changes (new data typed in Textbox?)<br />
for(li=0;li<lTelephone[0].keys.Length;li++)<br />
{<br />
  if (lTelephone[0].keys[li].keyId==1)<br />
  {<br />
    if (lTelephone[0].keys[li].telephoneNo!=txtNameKey01.Text)<br />
	// assign the changed number to an array containing all changed fields<br />
  }<br />
  // once again repeated for every 12 TextBoxes<br />
}

But well this isn't nice Frown | :(

and even harder to change lets say to 24 TextBoxes, but well it works Wink | ;)

. What I do want to do now is change the thing above to something like

// for displaying<br />
for(li=0;li<ldata[0].keys.Length;li++)<br />
{<br />
   //TextBox should be the "general" object<br />
   //ID of this "general" object should be the keyID<br />
   TextBox=ldata[0].keys[li].telnumber;<br />
}

The pseudocode above and beneeth should describe what I want to do. I do want to create a general object/variable/... whatever to just having to assign or compare in one statement. I do want the keyID to describe where the data should be sent to or which fielddata should be compared to.
With strings you are able to copy parts together like "hello"+"world"+year.ToString() => hello world 2004 but this doesn't work with assignments, does it? Unsure | :~

// for comparing for changed numbers<br />
for(li=0;li<lTelephone[0].keys.Length;li++)<br />
{<br />
  //TextBox once again a "general" object<br />
  if (lTelephone[0].keys[li].telephoneNo!=TextBox.Text)<br />
     //assign the changed number somewhere for further use		<br />
}

in the pseudocode above once again it should be using the keyID to decide which TextBox I am really doing the comparison with.

But at the moment I do wonder if this is really possible or if I have to live with this if-statements and with tons of code for comparison and assignments! OMG | :OMG:

Thanks!
Stephan.

Re: howto generalise compareoperations?

Daniel Turini28-Jul-04 1:53

Daniel Turini

28-Jul-04 1:53

If I got it right, you can easily do it by creating an array and put references to your textboxes there:

<br />
TextBox []theArray = { TextBox1, TextBox2, TextBox3, ..., TextBox12 };<br />

Then your if becomes

<br />
if (lTelephone[0].keys[li].telephoneNo!=theArray[i].Text)<br />

If an Array is not enough, you can use a Hashtable, an ArrayList, and so on.
People often overlook the fact that controls are simply objects like any other object.

Yes, even I am blogging now!

Re: howto generalise compareoperations?

Stephan Wright28-Jul-04 2:16

Stephan Wright

28-Jul-04 2:16

Thanks, it works!

I could have thought about this (enumbering the elements) myself, especially after having read it when trying to find a solution but throwing it away thinking it doesn't fit in here! Big Grin | :-D

Stephan.

Do MS Collection Class Enumerators use strong reference to keep collection alive?

Paul Evans28-Jul-04 1:29

Paul Evans

28-Jul-04 1:29

Hi there,
One of you bright sparks will know this off the top of your head (any supporting links you have greatful!)

Question: Do MS Collection Class Enumerators use strong reference to keep collection alive?

Background: Want to create collection in delegate function and set IEnumerator references from the parameters of the function to collections created in the function. This is so the delegate can use whatever collection it likes internally - as long as I can enumerate through the results on the other side it doesn't matter.

If MS use Weak Reference in enumerators then that would mean the collection isn't guarnteed to still be there when I go to use the IEnumerators. If it's a normal strong reference then that should keep the collection safe from the clutches of the GC.

Thoughts and answers greatly appreciated!

/**********************************
Paul Evans, Dorset, UK.
**********************************/

Re: Do MS Collection Class Enumerators use strong reference to keep collection alive?

Daniel Turini28-Jul-04 1:55

Daniel Turini

28-Jul-04 1:55

As a tip, use Reflector to decompile System.Collection classes and understand it better.

Yes, even I am blogging now!

License Key Create / Validate for windows Application

wcoods28-Jul-04 0:42

wcoods

28-Jul-04 0:42

Hi all,

i am writing a small custom windows forms application in c# which will ultiamtely be for sale - i hope Smile | :)

i am wondering...when i have created the application i want to control access to it via a license key which i could provide. the user could enter this and it will (validate) and allow them to legally use this software. i want it to be a one of license key validation.

as i am new to c# please excuse my lack of knowledge - can anyone give me any tips on how to handle the above? i have noticed the license manager and License Provider key words but i am unsure where to start Frown | :(

i would like to have some sort of initial entry window allowing my key i provide to be used only on that host pc...i.e. i want to somehow tie the license key to the host when they first install??...

any advice/code/tips no matter how small is appreciated

Re: License Key Create / Validate for windows Application

Heath Stewart28-Jul-04 4:39

Heath Stewart

28-Jul-04 4:39

There are so many ways of doing this, but you really need to research the problem. Keep in mind that anything a user installs on their local machine is possible to crack. All you can do is make it hard for them. Unfortunately, due to the nature of .NET assemblies, they can be disassembled, changed, and reassembled. Even relying on a native executable (C/C++ DLL) can be gotten around by disassembling the .NET assembly into IL, removing the call(s) to your native executable, and reassembling it (all using tools provided even in the .NET Framework SDK).

The LicenseProvider and related classes are more for design-time components (although a runtime option exists, I'm not sure it's currently supported). You can read more about these in the .NET Framework SDK (just type "LicenseProvider" in the .NET Framework SDK documentation that is installed with the .NET Framework SDK, which is installed by default with VS.NET).

I wrote an article you might want to take a look at, entitled Using XML Digital Signatures for Application Licensing[^]. This is one way you can implement both design-time and runtime licensing (though the actual implementation is up to you, but I do discuss various methods).

There are many others.

For instance, there is a pretty good library we evaluated from XHEO[^] that does - for some types of licensing it supports - use a similar idea for what I wrote about above. It also supports going out to a server on the 'net and verifying a license (a little more secure, but once again that could be removed if disassembled).

Basically, what I'm trying to say is that .NET applications are nearly as secure as natively compiled applications (decompiling these is extremely difficult and can only be done with best-guest mechanisms that are a long way from complete). All you can do is make it hard for the user and keep in mind that most users won't have the slightest clue about how to circumvent your application (though one crafty person could post how or post cracked binaries).

Microsoft MVP, Visual C#
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Finding File names from an Executable

Lee Majors27-Jul-04 23:19

Lee Majors

27-Jul-04 23:19

Hey,
This is my first post here, I am trying to find the name of a program given a .exe file.....I have been banging my head against this for the last few days and am alomst going insane.
Any help would be appreciated.

I have the full path of the file eg c:/windows/sample.exe and from this i am trying to get a program name that I can output for a user to see.

Cheers

Re: Finding File names from an Executable

Colin Angus Mackay28-Jul-04 0:17

Colin Angus Mackay

28-Jul-04 0:17

The simple answer is that you cannot.

What you see in the Start Menu and on icons in the Quick Launch bar and Desktop are the result of shortcuts (.lnk files)

If you are the author of the programs then you can write a mechanism that will expose a user friendly name, otherwise there is no consistent or reliable way to do that for third party applications.

"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell

Can't manage to P/Invoke that Win32 API in .NET? Why not do interop the wiki way!

Re: Finding File names from an Executable

Lee C Baker28-Jul-04 0:56

Lee C Baker

28-Jul-04 0:56

Firstly, thanks for the quick response.

But surely, there must be a way.

I have retrived the icon using SHGetFileInfo() in shell32.dll, i have a full path name, etc...

Where and how, for instance, does XP get the description field in file properties when you right click on a file, or in this case executable? I know this information is only stored when running an NTFS, but even that would be a start.

Or where does the value for the registry entry in MUICache come from? I tried searching the registry for a reliable location, without any luck.

????

Thanks from,

Slowly going insane.....

Re: Finding File names from an Executable

Heath Stewart28-Jul-04 4:19

Heath Stewart

28-Jul-04 4:19

There is a way, but keep in mind that it may not be the actual application title. That is set by the application at runtime only and it could be hard-coded into their source, grabbed from a resource string, or just about anything else.

Some of the information displayed in a file's properties (in the "Version" tab for an executable) can be obtained from the FileVersionInfo class like so:

FileVersionInfo info = FileVersionInfo.GetFileVersionInfo(
  "%SystemRoot%\notepad.exe");
Console.WriteLine(info.ProductName);

See the documentation for the FileVersionInfo class in the .NET Framework SDK for more information.

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