cpp07.cpp

C++参考书

// Coded by plusir -- Jan.07.2003.
// Standard C++ Bible -- (P371-12-7)

#include <iostream>
#include <string>
using namespace std ;

class String
{
	public:
		String( char *s = NULL )
		{
			if ( s ) {
                sptr = new char[strlen( s ) + 1] ;
				strcpy( sptr, s ) ;
			}
			else
				sptr = NULL ;
		}

		~String( void )
		{
			delete [] sptr ;
		}

		void display( void ) const
		{
			cout << sptr << endl ;
		}

		char& operator [] ( int n )
		{
			return *( sptr + n ) ;
		}

		const char& operator[] ( int n ) const
		{
			return *( sptr + n ) ;
		}

	private:
		char *sptr ;
} ;

int main()
{
	String string1( "The ldes of March" ) ;
	string1.display() ;

	string1[4] = '1' ;
	string1[5] = '5' ;
	string1[6] = 't' ;
	string1[7] = 'h' ;
	string1.display() ;

	strncpy( &string1[4], "21st", 4 ) ;
	string1.display() ;

	const String string2( "Et tu, Brute?" ) ;
	for ( int i = 0; i < 13; ++i )
		cout << string2[i] ;

	return 0 ;
}