basic_string::compare
Realiza una comparación distingue entre mayúsculas y minúsculas con una cadena especificada para determinar si las dos cadenas son iguales o si uno es lexicográficamente menos que el otro.
int compare(
const basic_string<CharType, Traits, Allocator>& _Str
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const basic_string<CharType, Traits, Allocator>& _Str
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const basic_string<CharType, Traits, Allocator>& _Str,
size_type _Off,
size_type _Count
) const;
int compare(
const value_type* _Ptr
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const value_type* _Ptr
) const;
int compare(
size_type _Pos1,
size_type _Num1,
const value_type* _Ptr
size_type _Num2
) const;
Parámetros
_Str
La cadena que se compara con la cadena de operando._Pos1
El índice de la cadena de operando en la que la comparación se inicia._Num1
El número máximo de caracteres de la cadena del operando que se va a comparar._Num2
El número máximo de caracteres de la cadena de parámetro que se va a comparar._Off
El índice de la cadena de parámetro en la que la comparación se inicia._Count
El número máximo de caracteres de la cadena de parámetro que se va a comparar._Ptr
La C cadena que se va a comparar con la cadena de operando.
Valor devuelto
Un valor negativo si la cadena del operando es menor que la cadena de parámetro; cero si las dos cadenas son iguales; o un valor positivo si la cadena del operando es mayor que la cadena de parámetro.
Comentarios
Las funciones miembro de compare comparan cualquier todo o parte de las cadenas del parámetro y el operando dependiendo de las que en utilizado.
La comparación realizada distingue entre mayúsculas y minúsculas.
Ejemplo
// basic_string_compare.cpp
// compile with: /EHsc
#include <string>
#include <iostream>
int main( )
{
using namespace std;
// The first member function compares
// an operand string to a parameter string
int comp1;
string s1o ( "CAB" );
string s1p ( "CAB" );
cout << "The operand string is: " << s1o << endl;
cout << "The parameter string is: " << s1p << endl;
comp1 = s1o.compare ( s1p );
if ( comp1 < 0 )
cout << "The operand string is less than "
<< "the parameter string." << endl;
else if ( comp1 == 0 )
cout << "The operand string is equal to "
<< "the parameter string." << endl;
else
cout << "The operand string is greater than "
<< "the parameter string." << endl;
cout << endl;
// The second member function compares part of
// an operand string to a parameter string
int comp2a, comp2b;
string s2o ( "AACAB" );
string s2p ( "CAB" );
cout << "The operand string is: " << s2o << endl;
cout << "The parameter string is: " << s2p << endl;
comp2a = s2o.compare ( 2 , 3 , s2p );
if ( comp2a < 0 )
cout << "The last three characters of "
<< "the operand string\n are less than "
<< "the parameter string." << endl;
else if ( comp2a == 0 )
cout << "The last three characters of "
<< "the operand string\n are equal to "
<< "the parameter string." << endl;
else
cout << "The last three characters of "
<< "the operand string\n is greater than "
<< "the parameter string." << endl;
comp2b = s2o.compare ( 0 , 3 , s2p );
if ( comp2b < 0 )
cout << "The first three characters of "
<< "the operand string\n are less than "
<< "the parameter string." << endl;
else if ( comp2b == 0 )
cout << "The first three characters of "
<< "the operand string\n are equal to "
<< "the parameter string." << endl;
else
cout << "The first three characters of "
<< "the operand string\n is greater than "
<< "the parameter string." << endl;
cout << endl;
// The third member function compares part of
// an operand string to part of a parameter string
int comp3a;
string s3o ( "AACAB" );
string s3p ( "DCABD" );
cout << "The operand string is: " << s3o << endl;
cout << "The parameter string is: " << s3p << endl;
comp3a = s3o.compare ( 2 , 3 , s3p , 1 , 3 );
if ( comp3a < 0 )
cout << "The three characters from position 2 of "
<< "the operand string are less than\n "
<< "the 3 characters parameter string "
<< "from position 1." << endl;
else if ( comp3a == 0 )
cout << "The three characters from position 2 of "
<< "the operand string are equal to\n "
<< "the 3 characters parameter string "
<< "from position 1." << endl;
else
cout << "The three characters from position 2 of "
<< "the operand string is greater than\n "
<< "the 3 characters parameter string "
<< "from position 1." << endl;
cout << endl;
// The fourth member function compares
// an operand string to a parameter C-string
int comp4a;
string s4o ( "ABC" );
const char* cs4p = "DEF";
cout << "The operand string is: " << s4o << endl;
cout << "The parameter C-string is: " << cs4p << endl;
comp4a = s4o.compare ( cs4p );
if ( comp4a < 0 )
cout << "The operand string is less than "
<< "the parameter C-string." << endl;
else if ( comp4a == 0 )
cout << "The operand string is equal to "
<< "the parameter C-string." << endl;
else
cout << "The operand string is greater than "
<< "the parameter C-string." << endl;
cout << endl;
// The fifth member function compares part of
// an operand string to a parameter C-string
int comp5a;
string s5o ( "AACAB" );
const char* cs5p = "CAB";
cout << "The operand string is: " << s5o << endl;
cout << "The parameter string is: " << cs5p << endl;
comp5a = s5o.compare ( 2 , 3 , s2p );
if ( comp5a < 0 )
cout << "The last three characters of "
<< "the operand string\n are less than "
<< "the parameter C-string." << endl;
else if ( comp5a == 0 )
cout << "The last three characters of "
<< "the operand string\n are equal to "
<< "the parameter C-string." << endl;
else
cout << "The last three characters of "
<< "the operand string\n is greater than "
<< "the parameter C-string." << endl;
cout << endl;
// The sixth member function compares part of
// an operand string to part of an equal length of
// a parameter C-string
int comp6a;
string s6o ( "AACAB" );
const char* cs6p = "ACAB";
cout << "The operand string is: " << s6o << endl;
cout << "The parameter C-string is: " << cs6p << endl;
comp6a = s6o.compare ( 1 , 3 , cs6p , 3 );
if ( comp6a < 0 )
cout << "The 3 characters from position 1 of "
<< "the operand string are less than\n "
<< "the first 3 characters of the parameter C-string."
<< endl;
else if ( comp6a == 0 )
cout << "The 3 characters from position 2 of "
<< "the operand string are equal to\n "
<< "the first 3 characters of the parameter C-string."
<< endl;
else
cout << "The 3 characters from position 2 of "
<< "the operand string is greater than\n "
<< "the first 3 characters of the parameter C-string."
<< endl;
cout << endl;
}
Requisitos
encabezado: <cadena>
espacio de nombres: std