File in c++

Question

This code is a in cpp
Can someone explain it to me please?

fstream fp("courses.dat" , ios::out|ios::in|ios::binary);

if(!fp)
{
ofstream fp1("courses.dat" , ios::out|ios::binary);
fp1.close();
}

ifstream inj("j.txt" , ios::in);
if(!inj)
{
ofstream outj("j.txt" , ios::out);
int tempJ=0;
outj<<tempJ;
outj.close();
}

Answer 1

Myabe this can help you:

https://www.sololearn.com/learn/CPlusPlus/1920/
https://www.sololearn.com/learn/CPlusPlus/1921/

If not, tell us where you dont inderstand what is happening

Answer 2

Alexander Thiem
tnx Alexander Thiem those informations helped me a little
But i still have questions
First :can we write" if(inj.is_open())" instead of (!inj)? And if the answer is no can you explain me why?
And the second question is why we use flag ios::in ? I really don't understand the usage of these optional parameters (flags)
Sorry I'm new to cpp so I have so many questions

Answer 3

I think inj.is_open is similar to !inj, but you can probably test this out in code playground or an other code area.
In this case the file is opened with ios::in , which means that you can only read it....
These flags define how the file is open:
For example ios::trunc clears the file completely before opening it.

Hope I could help you

Answer 4

Alexander Thiem
Tnx for your help

Answer 5

you are welcome