C / C++ / MFC

3-Oct-06 8:57

I was always under the impression that const before or after a function delaration was the same, yet after trying it I get compile errors, so obviously I was wrong. Would somebody please explain the difference between these two declarations:

const TCHAR *GetCurrentHash ();

TCHAR *GetCurrentHash () const;

Re: usage of const

C^hris L^osinger3-Oct-06 9:41

C^hris L^osinger

3-Oct-06 9:41

"const" after a member function name means the function doesn't change any of the object's internal member variables.

"const" before the function name applies to the return value.

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Re: usage of const

Waldermort3-Oct-06 9:49

3-Oct-06 9:49

Ahhh, that makes perfect sense now. Thankyou.

Re: usage of const

ThatsAlok4-Oct-06 7:06

ThatsAlok

4-Oct-06 7:06

waldermort wrote:
TCHAR *GetCurrentHash () const;

but you can change any function local variable here!

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A CFileDialog Question

Jethro633-Oct-06 8:01

3-Oct-06 8:01

Greetings:

I need to launch a CFileDialog box but I need to implement special file name filtering. That is, I might filter with a file name extension like "TXT", however, I need to filter even further by excluding files that have certain sub-strings embedded in their names. The wild card method is not going to work here because I need to exclude file names that have certain characteristics, not include them. This requirement has been thrust upon me and I simply have to find a solution.

I can't see anything in the documentation that says you can do this.

Any suggestions?

Thank you,
Mark

David Crow3-Oct-06 8:49

David Crow

3-Oct-06 8:49

Jethro63 wrote:
This requirement...

Does it also include using CFileDialog?

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Jethro633-Oct-06 8:57

3-Oct-06 8:57

Hi David:

No, not necessarily. I am becoming resigned to the possibility that I'll just have to construct my own selection dialog. No big deal, just another little thing on the great-big pile.

But I was expecting (or hoping) that under the hood of CFileDialog, there might be a mechanism, an optional callback function perhaps, where each time the dialog was about to add another entry to the list box embedded in the dialog, the callback would first be called and you could use this callback to do any manner of screening that you need and say "yes" or "no" to adding the file. No such luck, apparently.

So, I'm open to suggestions but I need to get this done. It is a minor requirement in the grand scheme of things but I have already spent a lot of time trying to come up with a solution.

Thanks,
Mark

PJ Arends3-Oct-06 9:14

PJ Arends

3-Oct-06 9:14

Look up CDN_INCLUDEITEM in MSDN.

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Jethro633-Oct-06 9:19

3-Oct-06 9:19

That is exactly what I was looking for!
Thanks!
Mark

Waldermort3-Oct-06 9:19

3-Oct-06 9:19

Creating your own dialog would be the easier choice. You could also allow the CFileDialog to do it's job, then before showing it to the user, iterate through it's list box performing your own additional scan of the files. All you need to do is find the window handle to it's listbox, then use the normal api functions to remove items.

Jethro633-Oct-06 9:25

3-Oct-06 9:25

Does this dialog expose the handle to its list box? Is there not a risk of screwing things up? For example, maybe I can remove the entries from the list box but what if there is an under-lying collection (like, say, CStringArray) that contains the entries and these entries are not removed? The list box would become un-synchronized with the internal list...

Thank you,
Mark

Haroon Sarwar3-Oct-06 18:20

Haroon Sarwar

3-Oct-06 18:20

did CDN_INCLUDEITEM work for you? As I recall it does not quite work as you would first expect...

I needed to do exactly what you did, the only solution I could find was provided by Paul DiLascia:

http://msdn.microsoft.com/msdnmag/issues/03/10/CQA/

There doesn't seem to be any under-lying collection, as this solution worked fine for me...the only problem is in this solution is you're deleting unwanted files from the list after they have been added rather than just excluding them in the first place...

Waldermort3-Oct-06 19:33

3-Oct-06 19:33

Another similar option would be to populate the dialogs list with an obviously stupid file extension, then add the items yourself.

software protection

Aamir Mughal3-Oct-06 7:59

Aamir Mughal

3-Oct-06 7:59

Hi,

Is it possible to kill any process that uses a certain process' memory under Win32?

stay safe,

Aamir

David Crow3-Oct-06 8:38

David Crow

3-Oct-06 8:38

Aamir Mughal wrote:
...process that uses a certain process' memory...

Please explain. Confused | :confused:

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Waldermort3-Oct-06 8:59

3-Oct-06 8:59

You can kill any process, however processes generaly do not share the same memory (a memory mapped file being an exception).

Stephen Hewitt3-Oct-06 18:04

Stephen Hewitt

3-Oct-06 18:04

Another way is that both .EXEs can use a DLL which has a shared data segment.

Steve

Waldermort3-Oct-06 19:15

3-Oct-06 19:15

Another way is ReadProcessMemory and WriteProcessmemory Wink | ;)

Stephen Hewitt3-Oct-06 19:31

Stephen Hewitt

3-Oct-06 19:31

That's not technically shared memory: it's a way to acesss mrmory in another process that isn't shared.

Steve

Stephen Hewitt3-Oct-06 19:31

Stephen Hewitt

3-Oct-06 19:31

That's not technically shared memory: it's a way to acesss memory in another process that isn't shared.

Steve

Aamir Mughal4-Oct-06 0:37

Aamir Mughal

4-Oct-06 0:37

I am basically trying to make an anti-cheat tool for a certain program. So I mean how can I stop programs like trainers which modify the programs memory value at runtime?