C / C++ / MFC

The Value is not updated when Passing a char array by reference

2-Dec-09 1:46

Omnicoder wrote:
z_stream_s zs;
zs = *z_stream_in;

char dest(StackSizeOf(char));
strcpy(dest,zs.next_in*);

This code does not appear to make sense. I don't think you can set a z_stream_s to a reference as you are trying to do. Also strcpy() needs a pointer to an array for its source and destination fields. You have set the destination to a single character, and the source to an incomplete expresion.

manoharbalu1-Dec-09 22:53

manoharbalu

1-Dec-09 22:53

I am using VC6 win32 console application.
I have a function as follows:
void GetModelInfo(char *pModelName, char *pIC1, char *pIC2)
{

pModelName = "test";
pIC1 = "abc";
pIC2 = "abc123";

}

Code where the function is called:

{
char ModelName[30], IC1[30], IC2[30];
memset(ModelName,0,30);
memset(IC1,0,30);
memset(IC2,0,30);
GetModelInfo(ModelName, IC1, IC2);
}

After the function GetModelInfo is getting called the variables pModelName, pIC1, pIC2 are not getting updated with the values assigned inside the GetModelInfo function.

Please help me to find whats the problem

Re: The Value is not updated when Passing a char array by reference

Adam Roderick J1-Dec-09 23:13

Adam Roderick J

1-Dec-09 23:13

To get it updated either you have to use the the variables stored in heap
and allocate outside the function.
or
change the parameter as reference
void GetModelInfo(char *&pModelName, char *&pIC1, char *&pIC2)

Величие не Бога может быть недооценена.

Re: The Value is not updated when Passing a char array by reference

KingsGambit1-Dec-09 23:16

KingsGambit

1-Dec-09 23:16

You can use strcpy() function instead of assignment.

strcpy(pModelName, "test");

Re: The Value is not updated when Passing a char array by reference

Richard MacCutchan2-Dec-09 1:49

Re: The Value is not updated when Passing a char array by reference

2-Dec-09 1:49

You cannot set method parameters in this way, all this does is set the temporary parameters within GetModelInfo(). In order to return the information you will need to use some copy method into the destination arrays. Read your C reference guide on the use of pointers and parameter passing.

loyal ginger2-Dec-09 3:30

loyal ginger

2-Dec-09 3:30

They are not updated because inside GetModelInfo local copies of the variables (which represent the addresses of the character arrays) are assigned new values. Because they are simply copies the original contents of the variables are not changed.

To change the contents of the original arrays, you have to copy the text to the memory addresses like this:

void GetModelInfo(char *pModelName, char *pIC1, char *pIC2)
{
	memcpy(pModelName, "test", 30);
	memcpy(pIC1, "abc", 30);
	memcpy(pIC2, "abc123", 30);
}

That way they will be updated.

CListCtrl

Paulraj G1-Dec-09 21:55

Paulraj G

1-Dec-09 21:55

Hi...

Hi have two clasess. Class_A, Class_B.

Now i am having all the values in Class_B. But my listcontrol is in Class_A.

I have to set all the values from Class_B.

What is the procedure?

Thanks...

G.Paulraj

wangningyu1-Dec-09 22:02

wangningyu

1-Dec-09 22:02

I suppose that you want to access the other class's member variables , isn't it ?

you can use the new operation.

Cedric Moonen1-Dec-09 22:07

Cedric Moonen

1-Dec-09 22:07

What do you mean ? D'Oh! | :doh:

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Cedric Moonen1-Dec-09 22:07

Cedric Moonen

1-Dec-09 22:07

This really depends on how the different classes are used in your program. One approach would be to pass Class_B to Class_A and provide getters in Class_B, so that Class_A can retrieve the values and populate the list.

What kind of architecure are you using ? Are you using MFC ? If yes are you using a doc/view architecture ? Is the list part of your view ? You need to give a lot more details about your architecture in order for us to help.

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Paulraj G1-Dec-09 22:16

Paulraj G

1-Dec-09 22:16

Hi...

I am using MFC only.
Its based on ObjectARX. I am retrieving all the values in Class_B.
But my list control is class_A.

How to insert class_B values in Class_A control?

G.Paulraj

PDF File Zoomin [modified]

Cedric Moonen1-Dec-09 22:31

Cedric Moonen

1-Dec-09 22:31

So, what's wrong with my first suggestion ? Did you try to understand it at least ?

BTW, when somebody asks you for details about your program architecutre, repeating the same information you already posted in your first message doesn't add anything...

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Pryabu1-Dec-09 20:25

Pryabu

1-Dec-09 20:25

hi,

I want to show particular location in a pdf file while opening it. How to do this?

Thanks,

modified on Wednesday, December 2, 2009 3:16 AM

Re: PDF File Zoomin

Richard MacCutchan1-Dec-09 21:33

1-Dec-09 21:33

I am not sure what this has to do with C++, but ... If you are trying to do this with code then you will need to interpret the index of the PDF file, locate the data for the relevant page, and then format and display that data.

See the PDF specification documentation at Adobe[].

Re: PDF File Zoomin

Pryabu1-Dec-09 21:45

Pryabu

1-Dec-09 21:45

I have find some pdf parameters in net to open a pdf file in differenct formats.

Please chk this link:

http://partners.adobe.com/public/developer/en/acrobat/PDFOpenParameters.pdf[^]

Similarly, i used this parameters in ShellExecute function. But its not working.

ShellExecute(NULL, "open","c:\\test\\1.pdf#page=72&view=fitH,100",NULL, NULL, SW_MINIMIZE);

Thanks,

Re: PDF File Zoomin

Richard MacCutchan1-Dec-09 22:46

Refresh Database take time

1-Dec-09 22:46

Karthika85 wrote:
But its not working.

What isn't working? I cannot guess what the problem is.

MsmVc1-Dec-09 19:49

MsmVc

1-Dec-09 19:49

Hi All

I am creating database and then get database name and properties.Like this

QueryResultsPtr Qry;
DatabasesPtr spDatabases;
_SQLServer2Ptr spSQLServer;
Qry=spSQLServer->ExecuteWithResults((_bstr_t)"Create databse Testing",(LONG)"Create databse Testing".GetLength());
spDatabases = spSQLServer->Databases;
spDatabases->Refresh();

It's working fine.
But it's take too much time when cursor goes here

spDatabases = spSQLServer->Databases;
spDatabases->Refresh();

Can i save some time?If any suggestion plz give me.
Thanks in advance

acessing source data on a URL

solinb1-Dec-09 16:59

solinb

1-Dec-09 16:59

I'm a biochemist who needs to get some minimal bioinformatics done. I need a way to access data at a URL and do some simple manipulations. The program doesn’t need to be robust, it just needs to work. I'm looking for an easy way to access the info, copy it into a file, and move the next page.

I'm having a very hard time figuring out where to start here. I have very minimal coding experience. Any help is greatly appreciated.

N a v a n e e t h1-Dec-09 17:13

N a v a n e e t h

1-Dec-09 17:13

solinb wrote:
I need a way to access data at a URL and do some simple manipulations

You need to find a library that can request to a URL and return the response. POCO[^] has got a network library which can be used here.

Smile | :)

Best wishes,
Navaneeth

Garth J Lancaster1-Dec-09 17:55

Garth J Lancaster

1-Dec-09 17:55

why dont you look at 'curl' http://curl.haxx.se/[^]

- comes in a command line, windows version - you can 'get' pages/data etc, if you needed more I'm sure you could wrap scripting around it to for example dump pages/files to disk and parse them - or use the curl-library and drive it from a program

'g'

David Crow2-Dec-09 3:22

David Crow

2-Dec-09 3:22

solinb wrote:
I need a way to access data at a URL...

Can you elaborate? Are you wanting to download a file given its URL?

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

solinb2-Dec-09 6:18

solinb

2-Dec-09 6:18

The site I need to access has a table of proteins featuring links to their sequence data. I need to be able to go from protein to protein, into the pages with their sequence data, get the data, and move to the next to one. I need to save all of this in a way that keeps the two in order.

The later end of that I can handle, even with my very basic skill set, I am used to manipulating data from text files. I'm just trying to figure out how to access the data.

Thanks to every for your help above, but I really do need help getting properly oriented. Every resource I find explains how to do this in terms of other things I don't understand. I'd really like to learn, but I need to know where to start.

again, i'm not looking for anything particularly robust, it just has to work.