Split String into parts in c++ - c++

Question

I have just started learning c++ and I was thinking is their any way of splitting strings. Lemme make it more clear.
Suppose user enters the string, date of birth in the following format dd-mm-yy. Now I wish to store the date, month and year in 3 different variables. So how do I go about ??
P.S : I googled a bit and found that this can be accomplished using the boot::regex. But still, I was wondering if there was any easier way of doing the same. Being a beginner hampers me. :P
Anyways, Any help would be appreciated.
To Brief:
I want something like this.
Enter date: //Accept the date
22-3-17 //Input by user
Date : 22 //Output
Month: 3 //Output
Year : 17 //Output

Answer 1

You can use sscanf function:
http://en.cppreference.com/w/cpp/io/c/fscanf
#include <iostream>
#include <string>
using namespace std;
int main(int argc, const char * argv[]) {
string date;
cin>>date;
int day, month, year;
sscanf(date.c_str(), "%d-%d-%d", &day, &month, &year);
cout << day << ' ' << month << ' ' << year;
return 0;
}

Answer 2

There are different methods you could do this. For the 'easiest' way I would suggest using std::string::find() methods( http://www.cplusplus.com/reference/string/string/find/) in combination with std::string::substr() method (http://www.cplusplus.com/reference/string/string/substr/)
For the use of regex you do not need boost: http://www.cplusplus.com/reference/regex/

Answer 3

You can use the operator [] to get the characters of the string.
http://www.cplusplus.com/reference/string/string/operator[]/

Answer 4

Here is a full working program that has been compiled, built and successfully ran on an Intel Core 2 Quad Extreme running Windows 7 64-bit using Visual Studio 2015 Community edition that has retrieved the information the OP had asked for in a particular format, parsed the string of information or data appropriately, and displayed the results in the requested or required format.
stdafx.h
#ifndef STDAFX_H
#define STDAFX_H
#include <vector>
#include <algorithm>
#include <iterator>
#include <tchar.h>
#include <conio.h>
#include <string>
#include <iostream>
#include <iomanip>
enum ReturnCode {
RETURN_OK = 0,
RETURN_ERROR = 1,
}; // ReturnCode
#endif // STDAFX_H
stdafx.cpp
#include "stdafx.h"
Utility.h
#ifndef UTILITY_H
#define UTILITY_H
class Utility {
public:
static void pressAnyKeyToQuit();
static std::string toUpper( const std::string& str );
static std::string toLower( const std::string& str );
static std::string trim( const std::string& str, const std::string elementsToTrim = " \t\n\r" );
static unsigned convertToUnsigned( const std::string& str );
static int convertToInt( const std::string& str );
static float convertToFloat( const std::string& str );
static std::vector<std::string> splitString( const std::string& strStringToSplit, const std::string& strDelimiter, const bool keepEmpty = true );
private:
Utility(); // Private - Not A Class Object
Utility( const Utility& c ); // Not Implemented
Utility& operator=( const Utility& c ); // Not Implemented
template<typename T>
static bool stringToValue( const std::string& str, T* pValue, unsigned uNumValues );
template<typename T>
static T getValue( const std::string& str, std::size_t& remainder );
}; // Utility
#include "Utility.inl"
#endif // UTILITY_H
Utility.inl
// ----------------------------------------------------------------------------
// stringToValue()
template<typename T>
static bool Utility::stringToValue(const std::string& str, T* pValue, unsigned uNumValues) {
int numCommas = std::count(str.begin(), str.end(), ',');
if (numCommas != uNumValues - 1) {
return false;
}
std::size_t remainder;
pValue[0] = getValue<T>(str, remainder);
if (uNumValues == 1) {
if (str.size() != remainder) {
return false;
}
}
else {
std::size_t offset = remainder;
if (str.at(offset) != ',') {
return false;
}
unsigned uLastIdx = uNumValues - 1;
for (unsigned u = 1; u < uNumValues; ++u) {
pValue[u] = getValue<T>(str.substr(++offset), remainder);
offset += remainder;
if ((u < uLastIdx && str.at(offset) != ',') ||
(u == uLastIdx && offset != str.size()))
{
return false;
}
}
}
return true;
} // stringToValue
Utility.cpp
#include "stdafx.h"
#include "Utility.h"
// ----------------------------------------------------------------------------
// pressAnyKeyToQuit()
void Utility::pressAnyKeyToQuit() {
std::cout << "Press any key to quit" << std::endl;
_getch();
} // pressAnyKeyToQuit
// ----------------------------------------------------------------------------
// toUpper()
std::string Utility::toUpper(const std::string& str) {
std::string result = str;
std::transform(str.begin(), str.end(), result.begin(), ::toupper);
return result;
} // toUpper
// ----------------------------------------------------------------------------
// toLower()
std::string Utility::toLower(const std::string& str) {
std::string result = str;
std::transform(str.begin(), str.end(), result.begin(), ::tolower);
return result;
} // toLower
// ----------------------------------------------------------------------------
// trim()
// Removes Elements To Trim From Left And Right Side Of The str
std::string Utility::trim(const std::string& str, const std::string elementsToTrim) {
std::basic_string<char>::size_type firstIndex = str.find_first_not_of(elementsToTrim);
if (firstIndex == std::string::npos) {
return std::string(); // Nothing Left
}
std::basic_string<char>::size_type lastIndex = str.find_last_not_of(elementsToTrim);
return str.substr(firstIndex, lastIndex - firstIndex + 1);
} // trim
// ----------------------------------------------------------------------------
// getValue()
template<>
float Utility::getValue(const std::string& str, std::size_t& remainder) {
return std::stof(str, &remainder);
} // getValue <float>
// ----------------------------------------------------------------------------
// getValue()
template<>
int Utility::getValue(const std::string& str, std::size_t& remainder) {
return std::stoi(str, &remainder);
} // getValue <int>
// ----------------------------------------------------------------------------
// getValue()
template<>
unsigned Utility::getValue(const std::string& str, std::size_t& remainder) {
return std::stoul(str, &remainder);
} // getValue <unsigned>
// ----------------------------------------------------------------------------
// convertToUnsigned()
unsigned Utility::convertToUnsigned(const std::string& str) {
unsigned u = 0;
if (!stringToValue(str, &u, 1)) {
std::ostringstream strStream;
strStream << __FUNCTION__ << " Bad conversion of [" << str << "] to unsigned";
throw strStream.str();
}
return u;
} // convertToUnsigned
// ----------------------------------------------------------------------------
// convertToInt()
int Utility::convertToInt(const std::string& str) {
int i = 0;
if (!stringToValue(str, &i, 1)) {
std::ostringstream strStream;
strStream << __FUNCTION__ << " Bad conversion of [" << str << "] to int";
throw strStream.str();
}
return i;
} // convertToInt
// ----------------------------------------------------------------------------
// convertToFloat()
float Utility::convertToFloat(const std::string& str) {
float f = 0;
if (!stringToValue(str, &f, 1)) {
std::ostringstream strStream;
strStream << __FUNCTION__ << " Bad conversion of [" << str << "] to float";
throw strStream.str();
}
return f;
} // convertToFloat
// ----------------------------------------------------------------------------
// splitString()
std::vector<std::string> Utility::splitString( const std::string& strStringToSplit, const std::string& strDelimiter, const bool keepEmpty ) {
std::vector<std::string> vResult;
if ( strDelimiter.empty() ) {
vResult.push_back( strStringToSplit );
return vResult;
}
std::string::const_iterator itSubStrStart = strStringToSplit.begin(), itSubStrEnd;
while ( true ) {
itSubStrEnd = search( itSubStrStart, strStringToSplit.end(), strDelimiter.begin(), strDelimiter.end() );
std::string strTemp( itSubStrStart, itSubStrEnd );
if ( keepEmpty || !strTemp.empty() ) {
vResult.push_back( strTemp );
}
if ( itSubStrEnd == strStringToSplit.end() ) {
break;
}
itSubStrStart = itSubStrEnd + strDelimiter.size();
}
return vResult;
} // splitString
main.cpp
#include "stdafx.h"
#include "Utility.h"
int main () {
std::string date;
std::cout << "Enter Date in DD-MM-YY Format.\n" << std::endl;
std::getline( std::cin, date );
std::vector<std::string> vResults = Utility::splitString( date, "-" );
std::cout << "\nDate : " << vResults[0] << std::endl
<< "Month: " << vResults[1] << std::endl
<< "Year : " << vResults[2] << std::endl << std::endl;
Utility::pressAnyKeyToQuit();
return 0;
} // main