Using getline() with file input in C++

c++ getline
Ghost Repeater picture Ghost Repeater · Dec 23, 2013 · Viewed 112.8k times · Source

I am trying to do a simple beginner's task in C++. I have a text file containing the line "John Smith 31". That's it. I want to read in this data using an ifstream variable. But I want to read the name "John Smith" into one string variable, and then the number "31" into a separate int variable.

I tried using the getline function, as follows:

ifstream inFile;
string name;
int age;

inFile.open("file.txt");

getline(inFile, name); 
inFile >> age; 

cout << name << endl;
cout << age << endl;  

inFile.close();

The problem with this is that it outputs the entire line "John Smith 31". Is there a way I can tell the getline function to stop after it has gotten the name and then kind of "restart" to retrieve the number? Without manipulating the input file, that is?

Answer

Johan picture Johan · Dec 23, 2013

getline, as it name states, read a whole line, or at least till a delimiter that can be specified.

So the answer is "no", getlinedoes not match your need.

But you can do something like:

inFile >> first_name >> last_name >> age;
name = first_name + " " + last_name;

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