how to split a string on comma in C++ [duplicate]

Question

I have this code currently in which the user would enter a number for how many numbers they want in the array. followed by '12345' however about a second after writing it i realized this would only work if they entered number 0-9 anything in double figures or more wouldnt work.

int numberOfValues;
cout << "Please enter the amount of integers you want in the array" << endl;
cin >> numberOfValues;

int valuesArray[numberOfValues];
string valuesString;

cout << "Please Enter " << numberOfValues << " numbers" << endl;
cin>>valuesString;


for(int i = 0; i < numberOfValues; i++)
{
    valuesArray[i] = valuesString[i];
}
return valuesArray;

im thinking that the best way to do this would be for the user to enter numbers separated by a comma and to split them afterwards (iv done this same little porgram in java and trying to change it to C++ for my own personal learning) like in java i used string.split(",") i was wondering if there is anything similar in c++??

Answer 1

The simplest way I can think of would be to avoid reading to an intermediate string and let cin do the work for you:

std::vector<int> valuesArray;

int i = 0;
do {
    cin >> i;
    valuesArray.push_back(i);
} while (valuesArray.size() < numberOfValues && cin.get() == ',');

/* edit: You may need to consume a '\n', if you expect one, too: */
do {
    i = cin.get();
} while (i != '\n');

Answer 2

Use strtok. Documentation and example can be found Here

Answer 3

use combination of string::substr() and string::find(). Find the next comma charater and then find the substring from current location to next command character

Answer 4

It is not standard C++ string, but still, Qt's QString class provides a ready-to-use method QString::split(...) with support for stuff like regular expressions, options for split behavior, case sensitivity and whatnot...

Answer 5

I wrote a tokenizer time ago, hope it works for you:

std::vector<std::string> tokenize(const std::string &_line,const char *_delimeter)
{
    std::vector<std::string> Tokens;

    if(_line.empty()) return Tokens;

    std::string str;

    BOOST_FOREACH(char c,_line){
        if(c==*_delimeter)
        {
            Tokens.push_back(str);
            str.clear();
            continue;
        }
        str += c;
    }

    if(!str.empty())
        Tokens.push_back(str);

    return Tokens;
}

it is not efficient, but works for testing purpose.