Open file fopen() and print values

[Wolkec]

How can i open a file with fopen and print the values?

[tnga]

You should use fopen to open the file. It will return a file pointer that you may use to read the values (using fread) to your variables and then you may print the value of these variables, dude.

ps.: use fread if it's a binary file... if the file you want to read is text you may use fscanf, ok?

Best regards
TNGA

[Wolkec]

what pointer? And can you please post the code?

[Silent1Mezzo]

what pointer? And can you please post the code?

Heres how to do it in c++/c

We can't just give you the code though. How are you supposed to learn on your own?

[niskin]

You can open a file like this:

FILE *fp;
fp=fopen("example.txt", "r");

Then you can read the contents into variables using fscanf. Look up how to use fscanf because I don't want to give you all the source code as you won't learn that way. You need to look up file i/o as well. Here is a link to a useful site:

www.cprogramming.com

[mohsin]

You can open a file like this:

FILE *fp;
fp=fopen("example.txt", "r");

Then you can read the contents into variables using fscanf. Look up how to use fscanf because I don't want to give you all the source code as you won't learn that way. You need to look up file i/o as well. Here is a link to a useful site:

www.cprogramming.com

yes u can do so in order to open a file
"r" for read
for writing you can use "w"
for reading and writing you can use "w+"

[Silent1Mezzo]

yes u can do so in order to open a file
"r" for read
for writing you can use "w"
for reading and writing you can use "w+"

You can also append b to the end of any of the modes to do it in binary

"rb" read binary
"wb" write binary

This is just another piece of information :P

[Wolkec]

the file im trying to open has:
[USER]
Energy=50
Health=30

[COMPUTER]
Energy=100
Health=10


Now how do i use fscanf to display "User has " << Energy << " energy and " << Health << " health.";


If you know what i mean :)

[Wolkec]

i also don't understand %f %s
:(

[Meetee]

i also don't understand %f %s
:(

For that I suggest u to learn from the scratch... For now I can say %f indicates float value and %s indicates string :)

Regards

[Wolkec]

i know that u can save varible with &Var but i dont know what %s and %d is :S

[Wolkec]

oh, s & d are string and decimal integrer, but i dont know how to find Energy for User

[Meetee]

i know that u can save varible with &Var but i dont know what %s and %d is :S

What u r talking about is scanf function..!
Any variable is of certain type...integer, float, string, char, boolean etc... for integer-%d, flaot-%f, string-%s, char-%c and so on...!!

like if u want to print any integer..u can write like this

int Wolk = 5;
printf("%d",Wolk);

Cheers!! :))

[Wolkec]

uh.. Can you tell me how to read from a file that says:
[USER]
Energy=50
Health=30

[COMPUTER]
Energy=100
Health=10

Now, how do i search values for USER and display its energy and health, and same for computer

[Wolkec]

oh, and i can edit the file

[Meetee]

uh.. Can you tell me how to read from a file that says:
[USER]
Energy=50
Health=30

[COMPUTER]
Energy=100
Health=10

Now, how do i search values for USER and display its energy and health, and same for computer

That can be done. :))

Refer this link

You will get an idea of how to do this..!

Regards

[Wolkec]

ok, ill try :):)
Any other way to search stuff in []

[Meetee]

Let me be more clear.

 (from http://www.cplusplus.com/doc/tutorial/files.html)
// reading a text file
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
 
int main () {
  string line;
  ifstream myfile ("example.txt");
  if (myfile.is_open())
  {
    while (! myfile.eof() )
    {
      getline (myfile,line);
      /*here you can compare : line == "user" than take health and energy
      and apply logic accordingly*/
      cout << line << endl;
    }
    myfile.close();
  }
 
  else cout << "Unable to open file"; 
 
  return 0;
}
 

[Meetee]

should i use fgetstring?

getline (myfile,line) would work for that! where line is string read from myfile.

Good luck :)

PS Search on google..u will get gr8 help!

[Wolkec]

how do i take health and energy lol :S

[Wolkec]

and also, if i search for USER, that name might change later on, so how do i make string search for specific person

[Meetee]

and also, if i search for USER, that name might change later on, so how do i make string search for specific person

So you are making file having many users? Then also this loop will iterate until u get the person u want.

while (! myfile.eof() )
{
getline (myfile,line);
cout << line << endl;
}

[Meetee]

and also, if i search for USER, that name might change later on, so how do i make string search for specific person

So you are making file having many users? Then also this loop will iterate until u get the person u want.

while (! myfile.eof() )
{
getline (myfile,line);
COMPARISON
cout << line << endl;
}

Sorry for double posting!!!

[Wolkec]

so, basicly, that extracts the text, should i use if to compare the string?

[Wolkec]

so, loop inside loop, or somethink else?

[Meetee]

so, basicly, that extracts the text, should i use if to compare the string?

Yes, better you start implementing the suggestions given uptil now and you will find the way!!

Regards

[r035198x]

and also, if i search for USER, that name might change later on, so how do i make string search for specific person

You know you should really consider taking time to read a c++ tutorial on file handling. Getting the program to work might be cool but knowing how to get the program to work is even better.

[Wolkec]

How do i display the values of the users :S
lol :)

[Wolkec]

1 string for each type (health, energy)?

[Wolkec]

and how do i dislpay the user inside []

[r035198x]

and how do i dislpay the user inside []

I suggest you read my reply #27 above and follow the advice there.
This thread may soon be closed if you won't take the advice.

[Wolkec]

lol, this is as far as i got :(
plz point me to the right direction:

int main ()
{
    string line;
    ifstream fp("c:\\Vaja.ini");
    if (fp.is_open())
    {
        while (! fp.eof())
        {
            getline (fp, line);
                        if (line[0] == '[') {
                // this is player
 
            cout << line << endl;
            }
        }
        fp.close();
    }
    else cout << "Vaja.ini doesn't exist or it cant be opened.\n";
 
        system("PAUSE");
  return EXIT_SUCCESS;
}
 

and should i use string for each type (health, energy) or should i use loop:

[niskin]

[quote=Wolkec]lol, this is as far as i got :(
plz point me to the right direction:

int main ()
{
    string line;
                //code
    if (line[0] == '[') {
                //code
}
 

[quote]

You are treating line as if it is an array. Instead of:

string line;

Put:

char line[20]; //20 is just an example, you can have it any size you want

[Wolkec]

any other way? This one is hard :(

[Wolkec]

any other good way to search for user and then type his status?

[Silent1Mezzo]

any other way? This one is hard :(

Programmings not always easy :P Sometimes the best way to do something is the hardest. I would advise you first read a c++ tutorial because us just giving you the answers really isn't helping you.

[tnga]

any other way? This one is hard :(

Well, it's not that hard!

What you need to know is:

1. How to treat text files
Some people has already pointed you the right way. Read info on how to open a file using fopen and how to read strings using fscanf with %s into a char array.

2. How to read values from a char array
For example, if you want to get "USER" you should make somthing like this:

if (myarray[0]=="[") {
// get the USER string here until you find "]"
}
 

Best regards,

TNGA

[Wolkec]

can any1 try and type the whole code :S i tried everything and it didnt work :(:(

[tnga]

Dude, I think we can't do it... It goes against the forum rules.
We all want to help you, but the right way for you to learn is...learning
and not taking the full code!
Try to follow my tips, search for tutorials on how to treat files and char arrays.

Best regards,
TNGA

[Wolkec]

I said i tried every think i know, and it doesnt work :S

[tnga]

I said i tried every think i know, and it doesnt work :S

Yes, you'd better try to learn something new. How about reading some tutorials?
I gave you the road to track after you said it was too difficult. After that you said you've tried everything but it hasn't passed enough time for a normal being to search stuff and read.
So, I keep my advice on trying to search and learn that stuff.

Best regards,
TNGA

[niskin]

I've never seen this done before on thescripts, but I'm going to give you some code and you have to fill in the gaps. Each underscore represents 1 letter you need to fill in. So a series of four underscores means you need to type a four letter word:

#include <_stream> //note this underscore represents a missing letter as well!
#include <iostream>
 
using namespace std;
 
int main ()
{     
    _ _ _ _ line[50];
    _ _ _ _ _ _ _ _ fp("c:\\vaja.ini");
    if (fp.is_open())
    {     
                     _ _>> line;
                     _ _ _ _<< line << endl;
                     system("PAUSE"); //OR cin.get(); (cin.get() is better programming unless you specifically want the user to press any key not just enter)
    }
 
    if (!fp.is_open()) {
         _ _ _ _ << "Vaja.ini doesn't exist or it cant be opened.\n";
         system("PAUSE");
         }
}

[tnga]

Oh, dude, this is so cool!!!
That's why I love this site!
I think I know the answers! Lol

[r035198x]

I've never seen this done before on thescripts, but I'm going to give you some code and you have to fill in the gaps. Each underscore represents 1 letter you need to fill in. So a series of four underscores means you need to type a four letter word:

#include <_stream> //note this underscore represents a missing letter as well!
#include <iostream>
 
using namespace std;
 
int main ()
{     
    _ _ _ _ line[50];
    _ _ _ _ _ _ _ _ fp("c:\\vaja.ini");
    if (fp.is_open())
    {     
                     _ _>> line;
                     _ _ _ _<< line << endl;
                     system("PAUSE"); //OR cin.get(); (cin.get() is better programming unless you specifically want the user to press any key not just enter)
    }
 
    if (!fp.is_open()) {
         _ _ _ _ << "Vaja.ini doesn't exist or it cant be opened.\n";
         system("PAUSE");
         }
}

Ha. Too many smart alecs around here

[Silent1Mezzo]

I've never seen this done before on thescripts, but I'm going to give you some code and you have to fill in the gaps. Each underscore represents 1 letter you need to fill in. So a series of four underscores means you need to type a four letter word:

#include <_stream> //note this underscore represents a missing letter as well!
#include <iostream>
 
using namespace std;
 
int main ()
{     
    _ _ _ _ line[50];
    _ _ _ _ _ _ _ _ fp("c:\\vaja.ini");
    if (fp.is_open())
    {     
                     _ _>> line;
                     _ _ _ _<< line << endl;
                     system("PAUSE"); //OR cin.get(); (cin.get() is better programming unless you specifically want the user to press any key not just enter)
    }
 
    if (!fp.is_open()) {
         _ _ _ _ << "Vaja.ini doesn't exist or it cant be opened.\n";
         system("PAUSE");
         }
}

I'd like to buy a vowel.....'a'

[niskin]

lol how did u know it was a? =O

[tnga]

lol how did u know it was a? =O

What about an "h" ? =O

[niskin]

got it in 1, my friend

[tnga]

Hey, dude, I like the game....
But Wolvek never came back... =O