C / C++ / MFC

19-Jan-06 2:25

How to read an ascii matrix from file?
The bigger problem is that I don't know the columns and rows number.
So I have to read the data (fscanf) but at the same time I have to catch the carriage-return (but fscanf can't help me!!)

Another question:
I have a function, for this, that works well but only with known matrix dimension;
it use fscanf and FILE object. Is possible to do the same using CFile and/or CString? (i.e. there is a cast from CFile to FILE?)

Thanks

Have a nice code day Wink | ;)

Maximilien19-Jan-06 2:49

Maximilien

19-Jan-06 2:49

well, don't use fscanf, read one line at a time, one "column" at a time.

I assume that you know the delimiter for each column, so use strtok to get each item for a line; add it to your matrix.

you could also pre-process your file, count the number of columns in the first line ( all lines have the same number of elements ? ) and count the number of lines in the file, then allocate your matrix with those numbers and re-read the file.

Maximilien Lincourt
Your Head A Splode - Strong Bad

Russell^'19-Jan-06 3:07

19-Jan-06 3:07

Thank you,
you gave me very good ideas Wink | ;)

Have a nice code day Wink | ;)

David Crow19-Jan-06 2:53

David Crow

19-Jan-06 2:53

_Russell_ wrote:
...but at the same time I have to catch the carriage-return (but fscanf can't help me!!)

Sure it can. Why would you think otherwise?

_Russell_ wrote:
Is possible to do the same using CFile and/or CString?

Certainly.

_Russell_ wrote:
(i.e. there is a cast from CFile to FILE?)

Why bother using a CFile object then? In any case, no such conversion exists.

"The words of God are not like the oak leaf which dies and falls to the earth, but like the pine tree which stays green forever." - Native American Proverb

Russell^'19-Jan-06 3:02

19-Jan-06 3:02

Hi David,

DavidCrow wrote:
Sure it can

let me understand: is there a way (using fscanf) to read a number from file and at the same time know if the CR is passed ?
Please, be more clear, and all my problems are solved. Big Grin | :-D

Thanks for your help Rose | [Rose]

Have a nice code day Wink | ;)

David Crow19-Jan-06 3:30

David Crow

19-Jan-06 3:30

_Russell_ wrote:
is there a way (using fscanf) to read a number from file...

Yes.

int num;
FILE *pFile;
fscanf(pFile, "%d", &num);

_Russell_ wrote:
...and at the same time know if the CR is passed ?

What exactly do you mean by this? If you wish to read a line of text from a file, including the newline character, use fgets().

"The words of God are not like the oak leaf which dies and falls to the earth, but like the pine tree which stays green forever." - Native American Proverb

Stephen Hewitt19-Jan-06 3:07

Stephen Hewitt

19-Jan-06 3:07

Here's one way to do it with STL (I know you asked for MFC, sorry). It doesn't actually store anything but it shows the basic structure.

#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
using namespace std;

int main(int argc, char* argv[])
{
ifstream fs("C:\\a.txt");

string line;
while ( getline(fs, line) )
{
stringstream ss(line);

string word;
while ( ss >> word )
{
cout << word << " ***END OF WORD*** ";
}

cout << "***END OF LINE***" << endl;
}

return 0;
}

Nice and clean and it works on any system with a standard compliant C++ compiler.

Steve

Russell^'19-Jan-06 4:22

19-Jan-06 4:22

Thank you friends
I solved it! Smile | :)

Have a nice code day Wink | ;)

TCHAR* and LPTSTR

kelprinc19-Jan-06 1:10

19-Jan-06 1:10

Does anybody know how to assign a TCHAR* fromo a LPTSTR.
This is my code:

p->shi502_netname ="test";<br />
LPTSTR h =p->shi502_netname ;<br />
TCHAR* var = h;<br />
<br />
cout<<var<<endl;

output: t

when I try to print out h i get the first letter of string pointed to by h;
I thing im no accessing the string from the pointer correctly

Kelvin Cikomo

Owner drawn19-Jan-06 1:18

19-Jan-06 1:18

kelprinc wrote:
p->shi502_netname ="test";

_tcscpy(p->shi502_netname, _T("test"));

I think you should copy _T("test") to "p->shi502_netname".

Now it should work.

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--Never say quits
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kelprinc19-Jan-06 1:25

19-Jan-06 1:25

It did not work
I think i shld rephrase my question.

I want to access the string being pointed to by shi502_netname
i.e if i just type

cout<<p->shi502_netname<

Owner drawn19-Jan-06 1:30

19-Jan-06 1:30

kelprinc wrote:

TCHAR * shi502_netname = _T("test");
LPTSTR h = shi502_netname ;
TCHAR* var = h;

cout<<var<<endl;
< blockquote="">

Here this is printing fine.

What is this p->shi502_netname. Is this a pointer to a char or a single char.

Jesus Loves
<marquee direction="up" height="40" scrolldelay="1" step="1" scrollamount="1" style="background:#aabbcc;border-bottom:thin solid 1px #6699cc">
--Owner Drawn
--Nothing special
--Defeat is temporary but surrender is permanent
--Never say quits
--Jesus is Lord

kelprinc19-Jan-06 1:38

19-Jan-06 1:38

We are on totally different wave lengths.

Forget about the first part. Assume you have a struct p that has shi502_netname as its member. shi502_netname is of type LPTSTR.

now i want to print the LPTSTR string in the p struct.

I tried doing this p->shi502_netname, but all i get is the first letter of the string

Kelvin Chikomo

Owner drawn19-Jan-06 1:43

19-Jan-06 1:43

I also declared a struct and put a member inside with the same name and it's still working.

struct 
{
	LPTSTR  shi502_netname;
}p;

p.shi502_netname = _T("test");
LPTSTR h = p.shi502_netname ;	
TCHAR* var = h;
cout<<var<<endl;

Here is the code. It's working. Sniff | :^)

Jesus Loves Rose | [Rose]

<marquee direction="up" height="40" scrolldelay="1" step="1" scrollamount="1" style="background:#aabbcc;border-bottom:thin solid 1px #6699cc">
--Owner Drawn Rose | [Rose]

--Nothing special
--Defeat is temporary but surrender is permanent
--Never say quits
--Jesus is Lord Rose | [Rose]

kelprinc19-Jan-06 1:46

19-Jan-06 1:46

I have edited the struct, its not a normal struct (typedef)

typedef struct
{
LPTSTR shi502_netname;
}p;

p.shi502_netname = _T("test");
LPTSTR h = p.shi502_netname ;
TCHAR* var = h;cout<

Owner drawn19-Jan-06 1:50

19-Jan-06 1:50

typedef struct 
{
	LPTSTR  shi502_netname;
}p;

Did you declare a variable of type p.

p p1; //don't forget this
p1.shi502_netname = _T("test");
LPTSTR h = p1.shi502_netname ;
TCHAR* var = h;
cout<<var<<endl;

It still works fine.

Jesus Loves Rose | [Rose]

<marquee direction="up" height="40" scrolldelay="1" step="1" scrollamount="1" style="background:#aabbcc;border-bottom:thin solid 1px #6699cc">
--Owner Drawn Rose | [Rose]

--Nothing special
--Defeat is temporary but surrender is permanent
--Never say quits
--Jesus is Lord Rose | [Rose]

kelprinc19-Jan-06 1:55

19-Jan-06 1:55

Yes i do. you did not declare yours as *p look at my definition of my struct below

typedef struct
{
LPTSTR shi502_netname;
}*p;

p p1; //don't forget thisp1.shi502_netname = _T("test");LPTSTR h = p1.shi502_netname ;TCHAR* var = h;cout<

Owner drawn19-Jan-06 2:01

19-Jan-06 2:01

Aha here is the problem...

typedef struct 
{
	LPTSTR  shi502_netname;
} ap,*p;

ap a;
p p1 = &a;
p1->shi502_netname = _T("test");
LPTSTR h = p1->shi502_netname ;
TCHAR* var = h;
cout<<var<<endl;

It works with the modifications that I made. You have to make another typedef along with *p i.e ap. If you don't what are you going to assign to a variable of type p. p needs an address of a struct of it's own type.

An advice: Please provide some meaningful names for variables and specially typedefs.

Jesus Loves Rose | [Rose]

<marquee direction="up" height="40" scrolldelay="1" step="1" scrollamount="1" style="background:#aabbcc;border-bottom:thin solid 1px #6699cc">
--Owner Drawn Rose | [Rose]

--Nothing special
--Defeat is temporary but surrender is permanent
--Never say quits
--Jesus is Lord Rose | [Rose]

kelprinc19-Jan-06 2:11

19-Jan-06 2:11

I tried it it did not work

the struct that iam using is part of the C++ libraries

here it is
typedef struct _SHARE_INFO_502 {
LPTSTR shi502_netname;
DWORD shi502_type;
LPTSTR shi502_remark;
DWORD shi502_permissions;
DWORD shi502_max_uses;
DWORD shi502_current_uses;
LPTSTR shi502_path;
LPTSTR shi502_passwd;
DWORD shi502_reserved;
PSECURITY_DESCRIPTOR shi502_security_descriptor;
} SHARE_INFO_502, *PSHARE_INFO_502, *LPSHARE_INFO_502;

And i have to use *PSHARE_INFO_502 as the name of the struct

Kelvin Chikomo

Owner drawn19-Jan-06 2:18

19-Jan-06 2:18

Go ahead it will work.

PSHARE_INFO_502 should take the address of a valid structure of the same type. Then it has to work.

Probably like this:

SHARE_INFO_502 shInfo;
PSHARE_INFO_502 pShInfo = &shInfo;

Now use pShInfo as you should.

Jesus Loves Rose | [Rose]

<marquee direction="up" height="40" scrolldelay="1" step="1" scrollamount="1" style="background:#aabbcc;border-bottom:thin solid 1px #6699cc">
--Owner Drawn Rose | [Rose]

--Nothing special
--Defeat is temporary but surrender is permanent
--Never say quits
--Jesus is Lord Rose | [Rose]

kelprinc19-Jan-06 2:27