basic_string::compare
Compare une chaîne avec une chaîne spécifiée pour déterminer si les deux chaînes sont égales, si l'une est lexicographiquement inférieure à l'autre, en respectant la casse.
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;
Paramètres
_Str
La chaîne qui doit être comparée à la chaîne d'opérande._Pos1
L'index de la chaîne opérande auquel la comparaison démarre._Num1
Le nombre maximal de caractères de la chaîne d'opérande à comparer._Num2
Le nombre maximal de caractères à utiliser à partir du paramètre de chaîne à comparer._Off
L'index du paramètre de chaîne à partir duquel la comparaison commence._Count
Le nombre maximal de caractères à utiliser à partir du paramètre de chaîne à comparer._Ptr
La C-string qui doit être comparée à la chaîne d'opérande.
Valeur de retour
Une valeur négative si la chaîne d'opérande est inférieure à la chaîne de paramètre ; zéro si les deux chaînes sont égales ; ou une valeur positive si la chaîne d'opérande est supérieure à la chaîne de paramètre.
Notes
Les fonctions membres compare comparent soit l'ensemble soit une partie des chaînes de paramètres et d'opérandes selon lesquelles sont utilisées.
La comparaison respecte la casse.
Exemple
// 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;
}
Configuration requise
En-tête : <chaîne>
Espace de noms : std