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What's the best way to trim std::string?

I'm presently utilizing the accompanying code to right-trim all the std::strings in my projects:
std::string s;

s.erase(s.find_last_not_of(" \n\r\t")+1);

It turns out great, yet I keep thinking about whether there are some end-cases where it might fail?
trim string cpp
by

2 Answers

espadacoder11
Using Boost's string algorithms would be easiest:


#include <boost/algorithm/string.hpp>



std::string str("hello world! ");

boost::trim_right(str);

str is now "hello world!". There's also trim_left and trim, which trims both sides.
sandhya6gczb
Here is the program to trim data.


#include <algorithm> 

#include <cctype>

#include <locale>



// trim from start (in place)

static inline void ltrim(std::string &s) {

    s.erase(s.begin(), std::find_if(s.begin(), s.end(), [](unsigned char ch) {

        return !std::isspace(ch);

    }));

}



// trim from end (in place)

static inline void rtrim(std::string &s) {

    s.erase(std::find_if(s.rbegin(), s.rend(), [](unsigned char ch) {

        return !std::isspace(ch);

    }).base(), s.end());

}



// trim from both ends (in place)

static inline void trim(std::string &s) {

    ltrim(s);

    rtrim(s);

}



// trim from start (copying)

static inline std::string ltrim_copy(std::string s) {

    ltrim(s);

    return s;

}



// trim from end (copying)

static inline std::string rtrim_copy(std::string s) {

    rtrim(s);

    return s;

}



// trim from both ends (copying)

static inline std::string trim_copy(std::string s) {

    trim(s);

    return s;

}

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