C / C++ / MFC

24-Mar-09 3:04

brucewayn wrote:
Can you give give me a good tutorial about device driver programming...

This is about as good as it gets.

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UrlDownloadtofile

p_196023-Mar-09 21:45

p_1960

23-Mar-09 21:45

HI ,
im using UrlDownloadtofile() to download some files ...but the issue is if the file is present im able to download file(With return value S_OK) ...but if the server is not accessible ie (some issue with IIS or any other..) or if the file is not present im not getting the exact return value from UrlDownloadtofile to specify to user whether it is server issue or File not present...in MSDN it was given that if the return value is INET_E_DOWNLOAD_FAILURE then file is not present in the server but...im getting some junk value like -2146697210...when the file is not present in the server or server is not accessible....

So please let me know how can i notify user what is the exact problem....

Sarath C23-Mar-09 22:20

Sarath C

23-Mar-09 22:20

As per the documentation, this function will return, either of the following values,
S_OK - 0
E_OUTOFMEMORY - 0x80000002
INET_E_DOWNLOAD_FAILURE - 0x800C0008

and from the error code you've given the value is negative which means that you're taking this values to a signed variable like int.

The actual return type is HRESULT and the values are defined with unsigned hexadecimal. Please compare it with INET_E_DOWNLOAD_FAILURE, S_OK or E_OUTOFMEMORY to know whether it has succeeded or not.

The error code you've given is close to INET_E_DOWNLOAD_FAILURE value. Please compare against it.

-Sarath.
"Great hopes make everything great possible" - Benjamin Franklin

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p_196023-Mar-09 22:45

p_1960

23-Mar-09 22:45

Thanks for ur reply .......i have changed view to Hexadecimal display...and now im getting return value as 0x800C0006...May i know what this return value indicates.....

David Crow24-Mar-09 3:07

24-Mar-09 3:07

p_1960 wrote:
May i know what this return value indicates.....

Have you tried errlook.exe?

p_196024-Mar-09 18:09

p_1960

24-Mar-09 18:09

May i know from where can i get that exe...?Is it a third party exe..

David Crow25-Mar-09 2:44

How to Check Dektop Window is the current Active Window?.

25-Mar-09 2:44

p_1960 wrote:
May i know from where can i get that exe...?

It comes with Visual Studio.

Nitheesh George23-Mar-09 20:59

Nitheesh George

23-Mar-09 20:59

Hi,

I am doing application in which i want to know whether the Desktop window is the current active window or Not. How can i do this. Is GetForeGroundWindow() is a solution?.

thanks

Nitheesh.

Jose Jo Martin

http://www.simpletools.co.in

Re: How to Check Dektop Window is the current Active Window?.

David Crow24-Mar-09 3:14

Re: How to Check Dektop Window is the current Active Window?.

24-Mar-09 3:14

Have you tried:

if (GetActiveWindow() == GetDesktopWindow())
    ...

Nitheesh George24-Mar-09 4:06

Nitheesh George

24-Mar-09 4:06

Hi David,

Thanks for your reply. I tried using the GetForeGroundWindow but that didn't work.

thanks

Nitheesh

Jose Jo Martin

http://www.simpletools.co.in

Re: How to Check Dektop Window is the current Active Window?.

David Crow24-Mar-09 5:58

Re: How to Check Dektop Window is the current Active Window?.

24-Mar-09 5:58

Assuming you meant GetForegroundWindow(), I don't recall suggesting it.

Anyway, what does it return? Have you compared that window handle with those in Spy++?

Nitheesh George25-Mar-09 5:03

Nitheesh George

25-Mar-09 5:03

Hi David,

I tried by using GetActiveWindow() but MSDN says

"The GetActiveWindow function retrieves the window handle to the active window attached to the calling thread's message queue." . So i am getting NULL when my application's window is not the current window.

Do u have any suggestion?.

thanks.

Nitheesh

Jose Jo Martin

http://www.simpletools.co.in

PropertySheet Not move.

Le@rner23-Mar-09 20:34

Le@rner

23-Mar-09 20:34

Hi all,

i m creating a propertysheet by using a class drived from property sheet.

its works fine but its not move.

please tell me wat can i do.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Re: PropertySheet Not move.

David Crow24-Mar-09 3:15

Re: writing to text files

24-Mar-09 3:15

"_$h@nky_" wrote:
its works fine but its not move.

Which means what?

writing to text files

Dercio23-Mar-09 19:48

Dercio

23-Mar-09 19:48

How do i write to a text file with out erasing the previous data on the same text file

Dercio@C++

Eytukan23-Mar-09 19:58

Eytukan

23-Mar-09 19:58

You should write it in append mode.

like in C++,

include<fstream>

std::ofstream ofs("mtfile.txt",ios::app);
ofs<<"Hi";
ofs.close()

ios::app says it's append mode. But just a question, Do you have a C++ book on hand?

He never answers anyone who replies to him. I've taken to calling him a retard, which is not fair to retards everywhere.-Christian Graus

Re: writing to text files

«_Superman_»23-Mar-09 23:39

«_Superman_»

23-Mar-09 23:39

In the fopen function set the mode parameter to "a" or "a+"

«_Superman_»
I love work. It gives me something to do between weekends.

passing by reference

Dercio23-Mar-09 19:45

Dercio

23-Mar-09 19:45

why do we sometimes need to pass by reference, a parameter of a function

Dercio@C++

Eytukan23-Mar-09 19:56

Eytukan

23-Mar-09 19:56

1.Passing by parameter ensures, you don't create multiple copies.
2.As you don't make copies, it saves memory and be faster.
3.When you change something to the reference, it would mean you are changing the actual object. So serves the purpose.
4. The same can be done using pointers, but reference are better in many ways. The major advantage is that you dont need to check for NULL every time.

He never answers anyone who replies to him. I've taken to calling him a retard, which is not fair to retards everywhere.-Christian Graus

Jijo.Raj23-Mar-09 19:59

Jijo.Raj

23-Mar-09 19:59

Hello Dercio,

1) To avoid creating unnecessary temporary copy of variable while calling functions.
2) More user friendly method than pointers to get data back from functions. For instance

void GetString( CString& Value ) 
{
   Value = "I've changed the value.";
}
...
CString csString;
GetString( csString );

Regards,
Jijo.

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led mike23-Mar-09 21:12

led mike

23-Mar-09 21:12

Dercio wrote:
why do we sometimes need to pass by reference, a parameter of a function

I will answer that question for you if you will answer my question.

Q: Why do people sometimes need to ask questions in internet forums for which there are massive amounts of existing information on the internet and in books which they could choose to read?

CPallini23-Mar-09 22:32

CPallini

23-Mar-09 22:32

Passing by reference is the sissy's way to pass a pointer.
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