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How to read a file with spaces in C++?


I started having C++ classes at university last week. At the moment I just know some C language which makes me a little confused when learning C++. I have this exercise that says: "Write and use the fstream library to read a text file. The function should write on the screen each text line read of the file (with spaces)."

I wrote the code below that can write the line but without spaces. I've also heard about getline, but I don't know how to use it, the compiler allways says "no matching function for call to getline".

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

file_read(){
    ifstream origem;
    origem.open("ficheiro.txt");


    if (!origem) {
        cerr << "Error" << endl;
        return -1;
    }
char outp[100];

while(!origem.eof() ){
    origem >> outp;
    cout << outp;
    }

return 0;
}

For example: If i have in the ficcheiro.txt"My dog has a bone", the programm will write it like "Mydoghasabone"

So with the getline I tried this:

...
    ifstream origem;
    origem.open("ficheiro.txt");


    if (!origem) {
        cerr << "Error" << endl;
        return -1;
}
    char outp[100];

    getline(origem, outp);
    origem >> outp;
    cout << outp;

    return 0;
}

The compiler said:[Error] no matching function for call to 'getline(std::ifstream&, std::char [100])'

My problem is just to read the file including the spaces!


I'm also having some trouble learning C++, I started learning 'Classes' and using the CMD and I don't even know what I'm learning. Do you know where can I learn C++ in a more understandable way?


Solution

  • Try this

    #include <iostream>
    #include <fstream>
    #include <string>
    
    using namespace std;
    
    int file_read()
    {
        ifstream origem;
        origem.open("ficheiro.txt");
    
    
        if (!origem) {
            cerr << "Error" << endl;
            return -1; 
        }
        char outp[100];
    
       while( origem.getline(outp,100) )
            cout << outp;
    
    return 0;
    }
    
    int main()
    {
        file_read();
    }
    

    The compiler said:[Error] no matching function for call to 'getline(std::ifstream&, std::char [100])'

    if you want to use getline() change outp from char to string like

    string outp;
    
    while( getline(origem,outp))
        cout << outp;
    

    Because getline() is for string.