std::basic_string::compare

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C++ Standard Library
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std::basic_string
Member functions basic_string::basic_string basic_string::operator= basic_string::assign basic_string::get_allocator Element access basic_string::at basic_string::operator[] basic_string::front (C++11) basic_string::back (C++11) basic_string::data basic_string::c_str Iterators basic_string::begin basic_string::cbegin (C++11) basic_string::end basic_string::cend (C++11) basic_string::rbegin basic_string::crbegin (C++11) basic_string::rend basic_string::crend (C++11) Capacity basic_string::empty basic_string::size basic_string::length basic_string::max_size basic_string::reserve basic_string::capacity basic_string::shrink_to_fit (C++11) Operations basic_string::clear basic_string::insert basic_string::erase basic_string::push_back basic_string::pop_back (C++11) basic_string::append basic_string::operator+= basic_string::compare basic_string::replace basic_string::substr basic_string::copy basic_string::resize basic_string::swap Search basic_string::find basic_string::rfind basic_string::find_first_of basic_string::find_first_not_of basic_string::find_last_of basic_string::find_last_not_of Constants basic_string::npos Non-member functions getline stoi stol stoll (C++11) (C++11) (C++11) stoul stoull (C++11) (C++11) stof stod stold (C++11) (C++11) (C++11) to_string (C++11) to_wstring (C++11)

int compare( const basic_string& str ) const;	(1)
int compare( size_type pos1, size_type count1,              const basic_string& str ) const;	(2)
int compare( size_type pos1, size_type count1,              const basic_string& str,              size_type pos2, size_type count2 ) const;	(3)
int compare( const CharT* s ) const noexcept;	(4)
int compare( size_type pos1, size_type count1,              const CharT* s ) const;	(5)
int compare( size_type pos1, size_type count1,              const CharT* s, size_type count2 ) const;	(6)

Compares two character sequences.

The first one (data) is a substring of the current string, the second one (arg) is a substring of a supplied character sequence. If sizes of the sequences do not match, the shorter sequence is considered being less than the longer sequence. If the sizes (size) of the sequences match, character values are compared. The comparison is done by calling Traits::compare(data, arg, size). For default strings this function does the comparison lexicographically.

Condition		Result	Return value
size(data) < size(arg)		data is less than arg	<0
size(data) == size(arg)	Traits::compare(data, arg, size) < 0	data is less than arg	<0
	Traits::compare(data, arg, size) == 0	data is equal to arg	​0​
	Traits::compare(data, arg, size) > 0	data is greater than arg	>0
size(data) > size(arg)		data is greater than arg	>0

1) Compares this string to str (data = *this, arg = str).

2) Compares a [pos1, pos1+count1) substring of this string to str (data = this->substr(pos1, count1), arg = str).

3) Compares a [pos1, pos1+count1) substring of this string to a substring [pos2, pas2+count2) of str (data = this->substr(pos1, count1), arg = str.substr(pos2, count2)}}).

4) Compares this string to the null-terminated character string pointed to by s (data = *this, arg = basic_string(s)).

5) Compares a [pos1, pos1+count1) substring of this string to the null-terminated character string pointed to by s (data = this->substr(pos1, count1), arg = basic_string(s)).

6) Compares a [pos1, pos1+count1) substring of this string to the first count2 characters of the character string pointed to by s (data = this->substr(pos1, count1), arg = basic_string(s, count2)). s can contain null characters.

Contents 1 Parameters 2 Return value 3 Example 4 See also

[edit] Parameters

str	-	other string to compare to
s	-	pointer to the character string to compare to
count1	-	number of characters of this string to compore
pos1	-	position of the first character in this string to compare
count2	-	number of characters of the given string to compore
pos2	-	position of the first character of the given string to compare

[edit] Return value

negative value if this string is less than the other character sequence, zero if the both character sequences are equal, positive value if this string is greater than the other character sequence.

[edit] Example

This section is incomplete

[edit] See also

substr	returns a substring (public member function)