basic_string::find_last_of
Searches through a string for the last character that matches any element of a specified string.
size_type find_last_of(
value_type _Ch,
size_type _Off = npos
) const;
size_type find_last_of(
const value_type* _Ptr,
size_type _Off = npos
) const;
size_type find_last_of(
const value_type* _Ptr,
size_type _Off,
size_type _Count
) const;
size_type find_last_of(
const basic_string<CharType, Traits, Allocator>& _Str,
size_type _Off = npos
) const;
Parameters
_Ch
The character value for which the member function is to search._Off
Index of the position at which the search is to finish._Ptr
The C-string for which the member function is to search._Count
The number of characters, counting forward from the first character, in the C-string for which the member function is to search._Str
The string for which the member function is to search.
Return Value
The index of the last character of the substring searched for when successful; otherwise npos.
Example
// basic_string_find_last_of.cpp
// compile with: /EHsc
#include <string>
#include <iostream>
int main( )
{
using namespace std;
// The first member function
// searches for a single character in a string
string str1 ( "abcd-1234-abcd-1234" );
cout << "The original string str1 is: " << str1 << endl;
basic_string <char>::size_type indexCh1a, indexCh1b;
static const basic_string <char>::size_type npos = -1;
indexCh1a = str1.find_last_of ( "d" , 14 );
if ( indexCh1a != npos )
cout << "The index of the last 'd' found before the 14th"
<< " position in str1 is: " << indexCh1a << endl;
else
cout << "The character 'd' was not found in str1 ." << endl;
indexCh1b = str1.find_first_of ( "x" );
if ( indexCh1b != npos )
cout << "The index of the 'x' found in str1 is: "
<< indexCh1b << endl << endl;
else
cout << "The character 'x' was not found in str1."
<< endl << endl;
// The second member function searches a string
// for a substring as specified by a C-string
string str2 ( "ABCD-1234-ABCD-1234" );
cout << "The original string str2 is: " << str2 << endl;
basic_string <char>::size_type indexCh2a, indexCh2b;
const char *cstr2 = "B1";
indexCh2a = str2.find_last_of ( cstr2 , 12 );
if (indexCh2a != npos )
cout << "The index of the last occurrence of an "
<< "element of 'B1' in str2 before\n the 12th "
<< "position is: " << indexCh2a << endl;
else
cout << "Elements of the substring 'B1' were not "
<< "found in str2 before the 12th position."
<< endl;
const char *cstr2b = "D2";
indexCh2b = str2.find_last_of ( cstr2b );
if ( indexCh2b != npos )
cout << "The index of the last element of 'D2' "
<< "after\n the 0th position in str2 is: "
<< indexCh2b << endl << endl;
else
cout << "The substring 'D2' was not found in str2 ."
<< endl << endl << endl;
// The third member function searches a string
// for a substring as specified by a C-string
string str3 ( "456-EFG-456-EFG" );
cout << "The original string str3 is: " << str3 << endl;
basic_string <char>::size_type indexCh3a;
const char *cstr3a = "5E";
indexCh3a = str3.find_last_of ( cstr3a , 8 , 8 );
if ( indexCh3a != npos )
cout << "The index of the last occurrence of an "
<< "element of '5E' in str3 before\n the 8th "
<< "position is: " << indexCh3a << endl << endl;
else
cout << "Elements of the substring '5G' were not "
<< "found in str3\n before the 8th position."
<< endl << endl;
// The fourth member function searches a string
// for a substring as specified by a string
string str4 ( "12-ab-12-ab" );
cout << "The original string str4 is: " << str4 << endl;
basic_string <char>::size_type indexCh4a, indexCh4b;
string str4a ( "ba3" );
indexCh4a = str4.find_last_of ( str4a , 8 );
if ( indexCh4a != npos )
cout << "The index of the last occurrence of an "
<< "element of 'ba3' in str4 before\n the 8th "
<< "position is: " << indexCh4a << endl;
else
cout << "Elements of the substring 'ba3' were not "
<< "found in str4\n after the 0th position."
<< endl;
string str4b ( "a2" );
indexCh4b = str4.find_last_of ( str4b );
if ( indexCh4b != npos )
cout << "The index of the last occurrence of an "
<< "element of 'a2' in str4 before\n the 0th "
<< "position is: " << indexCh4b << endl;
else
cout << "Elements of the substring 'a2' were not "
<< "found in str4\n after the 0th position."
<< endl;
}
The original string str1 is: abcd-1234-abcd-1234
The index of the last 'd' found before the 14th position in str1 is: 13
The character 'x' was not found in str1.
The original string str2 is: ABCD-1234-ABCD-1234
The index of the last occurrence of an element of 'B1' in str2 before
the 12th position is: 11
The index of the last element of 'D2' after
the 0th position in str2 is: 16
The original string str3 is: 456-EFG-456-EFG
The index of the last occurrence of an element of '5E' in str3 before
the 8th position is: 4
The original string str4 is: 12-ab-12-ab
The index of the last occurrence of an element of 'ba3' in str4 before
the 8th position is: 4
The index of the last occurrence of an element of 'a2' in str4 before
the 0th position is: 9
Requirements
Header: <string>
Namespace: std