Partager via


basic_string::resize

Spécifie une nouvelle taille d'une chaîne, l'ajout ou la suppression 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 des caractères ajoutés sont initialisés avec si des éléments supplémentaires sont nécessaires.

Notes

Si la taille résultante dépasse le nombre maximal de caractères, le formulaire est 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 : <string>

l'espace de noms : DST

Voir aussi

Référence

basic_string Class

basic_string::size et basic_string::resize