split function for C++

Question

Is there a split type function for C++ similar to Java? I know of ignore, but I don't quite understand it, and how it'll work for my case.

My input is:

{
  item = ball
  book = lord of the rings
  movie = star wars
}

My input given is an <attribute> = <value> and I have to store the two in different strings, or integers (depending on the value, for example, if its a number, use an integer).

What do you mean by 'ignore', and why do you think that templates have anything much to do with splitting strings? See the doc for std::string to see what it's got. — bmargulies, Sep 28 '11 at 12:20
@bmargulies there is a `str.split("=")` type function in the `java` API and there is a cin.ignore(1,"=")` type function in the `c++` API, I've tried using the ignore, but I'm lost in how to just get rid of the paranthese — SNpn, Sep 28 '11 at 12:23
possible duplicate of [How to split a string in C++?](http://stackoverflow.com/questions/236129/how-to-split-a-string-in-c) — Pablo Santa Cruz, Sep 28 '11 at 12:24
I think he can use the answer from that (I actually threw it in mine), but he could have been looking for something to just tokenize by the = sign which wouldn't be covered by that question - so I think it's a little different. — John Humphreys, Sep 28 '11 at 12:28

score 6 · Accepted Answer · answered Sep 28 '11 at 12:27

6

Use Boost::tokenizer as it does what you want to do. From the manual:

// simple_example_1.cpp
#include<iostream>
#include<boost/tokenizer.hpp>
#include<string>

int main(){
   using namespace std;
   using namespace boost;
   string s = "This is,  a test";
   tokenizer<> tok(s);
   for(tokenizer<>::iterator beg=tok.begin(); beg!=tok.end();++beg){
       cout << *beg << "\n";
   }
}

answered Sep 28 '11 at 12:27

Sardathrion - against SE abuse

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It works with icc and g++. Do you have boost installed? What is the error you are getting? – Sardathrion - against SE abuse Sep 28 '11 at 14:14

score 0 · Answer 2 · edited May 23 '17 at 11:51

0

Use strtok(): http://www.cplusplus.com/reference/clibrary/cstring/strtok/.

Just know that its not re-entrant because it uses an internal static variable, so don't call it twice in nested loops or anything like that.

and EDIT:

This is a very cool SO solution that would tokenize the whole string by spaces - you'd have to process the values back together after the = but it would teach you STL well :)

Split a string in C++?

edited May 23 '17 at 11:51

Community

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answered Sep 28 '11 at 12:24

John Humphreys

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If it's not re-entrant enough to call in nested loops it's definitely not thread safe - I figured anyone asking how to split a string didn't need to worry about that complexity though :p – John Humphreys Sep 28 '11 at 12:58
@w00te strtok won't work in my case...since I can have input similar to `item = baseball bat` and baseball bat has to be one string, strtok would split that up into two words – SNpn Sep 28 '11 at 13:27

split function for C++

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