Pointers and Objects Summary

You should note several points about using pointers to objects (refer to Figure 12.5 for a summary):

• You declare a pointer to an object by using the usual notation:

String * glamour;

• You can initialize a pointer to point to an existing object:

String * first = &sayings[0];

• You can initialize a pointer by using new. The following creates a new object:

String * favorite = new String(sayings[choice]);

Also see Figure 12.6 for a more detailed look at an example of initializing a pointer with new.

• Using new with a class invokes the appropriate class constructor to initialize the newly created object:

// invokes default constructor
String * gleep = new String;

// invokes the String(const char *) constructor
String * glop = new String("my my my");

// invokes the String(const String &) constructor
String * favorite = new String(sayings[choice]);

• You use the -> operator to access a class method via a pointer:

if (sayings[i].length() < shortest->length())

• You apply the dereferencing operator (*) to a pointer to an object to obtain an object:

if (sayings[i] < *first)    // compare object values
     first = &sayings[i];   // assign object address

Figure 12.5. Pointers and objects.

Figure 12.6. Creating an object with new.