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      std::wcstol,std::wcstoll

      From cppreference.com
      <cpp‎ |string‎ |wide
       
       
       
       
      Defined in header<cwchar>
      long      wcstol(constwchar_t* str,wchar_t** str_end,int base);
      longlong wcstoll(constwchar_t* str,wchar_t** str_end,int base);
      (since C++11)

      Interprets an integer value in a wide string pointed to bystr.

      Discards any whitespace characters (as identified by callingstd::iswspace) until the first non-whitespace character is found, then takes as many characters as possible to form a validbase-n (where n=base) integer number representation and converts them to an integer value. The valid integer value consists of the following parts:

      • (optional) plus or minus sign
      • (optional) prefix (0) indicating octal base (applies only when the base is8 or0)
      • (optional) prefix (0x or0X) indicating hexadecimal base (applies only when the base is16 or0)
      • a sequence of digits

      The set of valid values for base is{0, 2, 3, ..., 36}. The set of valid digits for base-2 integers is{0, 1}, for base-3 integers is{0, 1, 2}, and so on. For bases larger than10, valid digits include alphabetic characters, starting fromAa for base-11 integer, toZz for base-36 integer. The case of the characters is ignored.

      Additional numeric formats may be accepted by the currently installed Clocale.

      If the value ofbase is0, the numeric base is auto-detected: if the prefix is0, the base is octal, if the prefix is0x or0X, the base is hexadecimal, otherwise the base is decimal.

      If the minus sign was part of the input sequence, the numeric value calculated from the sequence of digits is negated as if byunary minus in the result type.

      The functions sets the pointer pointed to bystr_end to point to the wide character past the last character interpreted. Ifstr_end is a null pointer, it is ignored.

      Contents

      [edit]Parameters

      str - pointer to the null-terminated wide string to be interpreted
      str_end - pointer to a pointer to wide character
      base -base of the interpreted integer value

      [edit]Return value

      Integer value corresponding to the contents ofstr on success. If the converted value falls out of range of corresponding return type, range error occurs andLONG_MAX,LONG_MIN,LLONG_MAX orLLONG_MIN is returned. If no conversion can be performed,0 is returned.

      [edit]Example

      Run this code
      #include <cwchar>#include <errno.h>#include <iostream>#include <string> int main(){constwchar_t* p= L"10 200000000000000000000000000000 30 -40";wchar_t* end;std::wcout<<"Parsing L'"<< p<<"':\n";for(long i= std::wcstol(p,&end,10); p!= end; i= std::wcstol(p,&end,10)){std::wcout<<'\''<<std::wstring(p, end-p)<<"' -> ";        p= end;if(errno==ERANGE){std::wcout<<"range error, got ";errno=0;}std::wcout<< i<<'\n';}}

      Possible output:

      Parsing L'10 200000000000000000000000000000 30 -40':'10' -> 10' 200000000000000000000000000000' -> range error, got 9223372036854775807' 30' -> 30' -40' -> -40

      [edit]See also

      converts a byte string to an integer value
      (function)[edit]
      converts a wide string to an unsigned integer value
      (function)[edit]
      C documentation forwcstol,wcstoll
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/string/wide/wcstol&oldid=161098"

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