C / C++ / MFC Discussion Boards

In this case, it also enables polymorphism, so that you can use pointers to objects whose type is a sub-type of CDC, such as CPrinterDC. CDC is a general device context wrapper, while CPrinterDC is specific to printers. This means that the same code can be used for any device context type.

There are several (general) reasons to use pointers (in some circumstaces), all covered by a good C++ book.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

For the same reason we use pointers anywhere else.

A pointer gives us access to the original data object, which can be huge, while using a simple variable means we have access to a local copy of the object, which involves copying all the data over, and any changes made to the local object are not reflected back to the original. We could of course use a reference to the original, but then that would remove the possibility of passing a NULL value.

You may be right
I may be crazy
-- Billy Joel --

Within you lies the power for good - Use it!

Hallo,
I have open a text file using file OPEN dialog menu, and i store the path using GetPathName(). File may choose from anywhere. Then I want to write something into a .txt file in my project directory when I open it ( MFC Application ). For this I have used fopen(".\\ProjectDireectory\\Temp.txt", "w"). It cant find the 'ProjectDirectory'. Programe stores the path from where i select the file for open.
I can not give the specic path because I dont know where it will stored.

Thanks.

Could you please explain more clearly what are your requirements?
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Actually i want to open a file from any directory and parallely i want to write a file in my Project directory(Exe directory). This directory may be anywhere in the disk. I want using '. notation' to write the file as because i dont know where the exe installed. I have given the example.

Does GetModuleFilename fit your needs?

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Also take a look at SHGetFolderPath(). Writing to files in the install directory can be problematic. (access rights and such)

You may be right
I may be crazy
-- Billy Joel --

Within you lies the power for good - Use it!

OK, I'll take a look: Who knows? someday maybe it will be useful... Roll eyes | :rolleyes:

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Hi All,

I need to get the item,which is double clicked in ListBox.I need sample code.

Thanks & Regards,

Anitha

Handle the LBN_DBLCLK notification.

"Love people and use things, not love things and use people." - Unknown

"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch

AnithaSubramani wrote:
I need sample code.

Documentation [^] isn't enough?
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

And this Simple Tutorial[^] too, which explains how to handle double click event for listbox.

Regards,
Jijo.

_____________________________________________________

http://weseetips.com[^] Visual C++ tips and tricks. Updated daily.

Hello everyone,

Since one of my .h file is included by multiple cpp files, and I want to track the compile process, so I want to have output during compiling phase each time when a cpp file which includes the .h file is compiled. And I also want to dump the compiled cpp file name.

For example, foo.cpp and goo.cpp includes common.h, when compiling foo.cpp, I want to output "foo.cpp is compiling" and when compiling goo.cpp, I want to output "goo.cpp is compiling".

I think I should use #pragma in common.h, but not an expert about this. Any ideas?

thanks in advance,
George

You can use like this,

#pragma message ("Compiling HelloWorld.cpp" )

Regards,
Jijo.

_____________________________________________________

http://weseetips.com[^] Visual C++ tips and tricks. Updated daily.

Thanks Jijo,

Put it in .cpp files or in the .h file?

regards,
George

What is your guess?
Poke tongue | ;-P

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Thanks CPallini,

I think it means adding information to each cpp file. It is not a good solution since it means I need to modify all source files which need to include the header file. Smile | :)

Any better ideas or comments?

regards,
George

The guess is right: you should put it into the header file.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Put what information? Could you clarify please? There is some context missing here. Smile | :)

regards,
George

Well, I was wrong (I took literally the documentation [^]
__FILE__

The name of the current source file.

but a little test clearified my misunderstanding Blush | :O

).

Hence, I suppose __FILE__ is of little help. As workaround, you may compile the source file with the /E switch and look at the generated output.

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Thanks CPallini,

My confusion is put __FILE__ into header file will output the value of .h file other than .cpp file. This is not I want. Smile | :)

I want to know which cpp file (that includes the .h file) is compiling currect. Any comments or ideas?

regards,
George

Can be in .h as well as in .cpp. It depends your need. Smile | :)

Regards,
Jijo.

_____________________________________________________

http://weseetips.com[^] Visual C++ tips and tricks. Updated daily.

Thanks Jijo,

I am confused about the discussion context. You mean put what information in .h file which could monitor which cpp file (that includes the .h file) is compiling?

regards,
George

Possibly

#pragma message("Compiling " __FILE__ )

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]