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basic_string::resize

Spécifie une nouvelle taille pour une chaîne, en ajoutant ou effaçant des éléments au besoin.

void resize(
    size_type _Count, 
);
void resize(
    size_type _Count,
    _Elem _Ch
);

Paramètres

  • _Count
    La nouvelle taille de la chaîne.

  • _Ch
    La valeur que les caractères ajoutés sont initialisés à si les éléments supplémentaires sont requis.

Notes

Si la valeur obtenue excède le nombre maximal de caractères, le format génère length_error.

Exemple

// basic_string_resize.cpp
// compile with: /EHsc
#include <string>
#include <iostream>

int main( ) 
{
   using namespace std;
   string  str1 ( "Hello world" );
   cout << "The original string str1 is: " << str1 << endl;

   basic_string <char>::size_type sizeStr1;
   sizeStr1 = str1.size ( );
   basic_string <char>::size_type capStr1;
   capStr1 = str1.capacity ( );

   // Compare size & capacity of the original string
   cout << "The current size of original string str1 is: " 
        << sizeStr1 << "." << endl;
   cout << "The capacity of original string str1 is: "
        << capStr1 << "." << endl << endl;

   // Use resize to increase size by 2 elements: exclamations
   str1.resize ( str1.size ( ) + 2 , '!' );
   cout << "The resized string str1 is: " << str1 << endl;

   sizeStr1 = str1.size ( );
   capStr1 = str1.capacity ( );

   // Compare size & capacity of a string after resizing
   cout << "The current size of resized string str1 is: " 
        << sizeStr1 << "." << endl;
   cout << "The capacity of resized string str1 is: "
        << capStr1 << "." << endl << endl;

   // Use resize to increase size by 20 elements:
   str1.resize ( str1.size ( ) + 20 );
   cout << "The resized string str1 is: " << str1 << endl;

   sizeStr1 = str1.size ( );
   capStr1 = str1.capacity ( );

   // Compare size & capacity of a string after resizing
   // note capacity increases automatically as required
   cout << "The current size of modified string str1 is: " 
        << sizeStr1 << "." << endl;
   cout << "The capacity of modified string str1 is: "
        << capStr1 << "." << endl << endl;

   // Use resize to downsize by 28 elements:
   str1.resize ( str1.size ( ) - 28 );
   cout << "The downsized string str1 is: " << str1 << endl;

   sizeStr1 = str1.size (  );
   capStr1 = str1.capacity (  );

   // Compare size & capacity of a string after downsizing
   cout << "The current size of downsized string str1 is: " 
        << sizeStr1 << "." << endl;
   cout << "The capacity of downsized string str1 is: "
        << capStr1 << "." << endl;
}
  

Configuration requise

En-tête : <chaîne>

Espace de noms : std

Voir aussi

Référence

basic_string, classe

basic_string::size et basic_string::resize