对码当歌,猿生几何?

std::basic_string::find_last_of

From cppreference.com
< cpp‎ | string‎ | basic string
 
 
 
std::basic_string
 
size_type find_last_of( const basic_string& str, size_type pos = npos ) const;
(1)
size_type find_last_of( const CharT* s, size_type pos, size_type count ) const;
(2)
size_type find_last_of( const CharT* s, size_type pos = npos ) const;
(3)
size_type find_last_of( CharT ch, size_type pos = npos ) const;
(4)
size_type find_last_of( std::basic_string_view<CharT, Traits> sv,
                        size_type pos = npos) const
(5) (since C++17)

Finds the last character equal to one of characters in the given character sequence. Exact search algorithm is not specified. The search considers only the interval [0; pos]. If the character is not present in the interval, npos will be returned.

1) Finds the last character equal to one of characters in str.
2) Finds the last character equal to one of characters in the first count characters of the character string pointed to by s. s can include null characters.
3) Finds the last character equal to one of characters in character string pointed to by s. The length of the string is determined by the first null character.
4) Finds the last character equal to ch.
5) Finds the last character equal to one of characters in sv.

In all cases, equality is checked by calling Traits::eq.

Parameters

str - string identifying characters to search for
pos - position at which the search is to finish
count - length of character string identifying characters to search for
s - pointer to a character string identifying characters to search for
ch - character to search for
sv - std::basic_string_view identifying the characters to search for

Return value

Position of the found character or npos if no such character is found.

Exceptions

1-4) (none)
(until C++11)
1,4)
noexcept specification:  
noexcept
  
2,3) (none)
(since C++11)
(until C++14)
1)
noexcept specification:  
noexcept
  
2,3,4) (none)
(since C++14)
5)
noexcept specification:  
noexcept
  
(since C++17)

Example

#include<string>
#include<iostream>
int main()
{
    const std::string path="/root/config";
    auto const pos=path.find_last_of('/');
    const auto leaf=path.substr(pos+1);
 
    std::cout << leaf << '\n';
}

Output:

config

See also

find characters in the string
(public member function)
find the last occurrence of a substring
(public member function)
find first occurrence of characters
(public member function)
find first absence of characters
(public member function)
find last absence of characters
(public member function)