Liren Large Software Subsidy 7/07.iso/c/c021/7.img/EXAMPLES.ZIP/XSTRING.CPP

C/C++ Source or Header | 1990-05-04 | 1.7 KB | 71 lines

//XSTRING.CPP--Example from Chapter 5 of Getting Started */
// version of STRING.CPP with overloaded operator +

#include <iostream.h>
#include <string.h>

class String {
   char *char_ptr;   // pointer to string contents
   int length;       // length of string in characters
public:
   // three different constructors
   String(char *text);           // constructor using existing string
   String(int size = 80);        // creates default empty string
   String(String& Other_String); // for assignment from another
                                 // object of this class
   ~String() {delete char_ptr;}; // inline destructor
   int Get_len (void);
   String operator+ (String& Arg);
   void Show (void);
};

String::String (char *text)
{
   length = strlen(text);  // get length of text
   char_ptr = new char[length + 1];
   strcpy(char_ptr, text);
};

String::String (int size)
{
   length = size;
   char_ptr = new char[length+1];
   *char_ptr = '\0';
};

String::String (String& Other_String)
{
   length = Other_String.length;       // length of other string
   char_ptr = new char [length + 1];   // allocate the memory
   strcpy (char_ptr, Other_String.char_ptr); // copy the text
};

String String::operator+ (String& Arg)
{
  String Temp( length + Arg.length );
  strcpy(Temp.char_ptr, char_ptr);
  strcat(Temp.char_ptr, Arg.char_ptr);
  return Temp;
}

int String::Get_len(void)
{
   return (length);
};

void String::Show(void)
{
   cout << char_ptr << "\n";
};

main ()                                // test the functions
{
   String AString ("The Quick Brown fox");
   AString.Show();

   String BString(" jumps over Bill");
   String CString;
   CString = AString + BString;
   CString.Show();
}