How can I write variables to .txt files?

Question

I am trying to make a program that saves changes or progress, by using fstream.

I searched online and found codes that were similar to what I need, but, I was not able to get what I wanted.

Here is the code or "puesdo code" that I worked from.

If you know how to save or store variables using fstream,

I would appreciate your input.

https://code.sololearn.com/c475wbkF190n/?ref=app

Answer 1

It will be best to have 3 functions here, create, read and write...

I also use this function for checking if the file exists or not:

bool exist(string path)
{
ifstream file;
file.open(path.c_str());
return bool(file);
}

Create: this will create a new file only if the player's data doesn't exist in the database...

void Create(string path)
{
if(!exist(path))
{
fstream fout;
fout.open(path.c_str());
fout<<1<<" "<<100<" "<<0<<endl;
fout.close();
}
}

Read: This will simply read the data from the save files...

void Read(string path,int& lvl,int& health,int& progress)
{
ifstream fin;
fin.open(path.c_str());
fin>>lvl>>health>>progress;
fin.close();
}

Write: This will overwrite the data to the file...

void write(string path,int lvl,int health,int progress)
{
ofstream fout;
fout.open(path.c_str(),ios::trunc);
fout<<lvl<<" "<<health<<" "<<progress;
fout.close();
}

This may help you...

Answer 2

@Kinshuk @Manual Guys, sorry for spamming, but you've just asked something similar to what I wanted to know. How do we append data to a file, without overwriting it?
In c, I would do something like:
FILE *f;
f= fopen ("fileName.txt" , at);
And I would do my thing with it... What is the equivalent in c++? Do you maybe know?

Answer 3

@Manual, what if there are more than one player in the game? For the given scenario binary mode should be more suitable. Moreover, it would be better reuse class or structure to represent your player.

Answer 4

@Devender

You are right.

I am tring to save or write small things,

before I write structures and or classes into files.

I will do that in a future project.

Answer 5

@Manual check this code. Does is it helpful?
https://code.sololearn.com/c6JRw8grXTk5/#cpp

Answer 6

So you simply want to read and write data from a file which can be altered even at runtime?

In my current Airline Reservation Program, I save the passenger data and the seats booked in a particular flight on a particular day in files so that the program may have access to these changes later as well...

In the seats part, for example, this helps me see if the flight is completely booked or not...

Do you need to achieve a similar thing?

Answer 7

Here are two references from a C++ forum.

about loading highscores:

http://www.cplusplus.com/forum/beginner/130571/

Answer 8

@Manual
If you have checked this:

https://code.sololearn.com/cLGN9A6ZdaHB/?ref=app

You can see that I have used similar functions like the one I gave you to maintain the game data...

//Sorry, but I am not trying to advertise my code, just sharing it as it uses the same thing...

//If you feel this as advertising, please let me know, Ill remove this answer then...

Answer 9

Here is the new version with the c and c++ bool headers so it compiles.

@Kinshuk

Thanks again!

https://code.sololearn.com/cKXNrY5ZRufU/#cpp

Answer 10

@dplusplus

I believe there is an append perameter that you can use.

I am still working on files and have not tried it I will add my reference to it.

Answer 11

@dplusplus

You are welcome!

Please let me know what you get from it.

I will be using those methods for files as well.

Answer 12

edit

Please post your references, if you are able.

I will post some as well.

Answer 13

@Manual
By sources, do you mean codes or reference sites?

Answer 14

@Kinshuk

You got it,

I am tring to make a code that can be altered at run time.

I am thing to find a way to store strings, ints and other values, alter them.

Then call the values, when I run the code again.

Answer 15

Here is the link for the tutorial on file handling.

http://www.cplusplus.com/doc/tutorial/files/

Answer 16

@Manual
And do note that path can be the username of the player, as it must be unique for all players to maintain data properly...

Answer 17

@Kinshuk

No, I appreciate that you shared your code to help me.

I do not feel it is advertising.

Thank you,for sharing it.

I recently started windows programming, and getting the file down should help.

Answer 18

@Kinshuk

Thank you very much!

I finished debugging the code and it compiled.

Answer 19

@dplusplus

Here is one, I hope it helps.

http://www.cplusplus.com/reference/fstream/ofstream/open/

Answer 20

@Manual
You're Welcome!
Glad to know that I could be helpful.