Teach Yourself Borland C++ in 14 Days - portal

NOTE
Wading In Deeper
You can create instances of a structure when you declare the structure.
At the end of the structure declaration, insert a variable name (one or
more) between the closing brace and the semicolon that follows the
structure declaration. Here’s an example:
struct point {
int x;
int y;
} upperLeft, lowerRight;
This code declares the structure and creates two instances of the
structure with variable names upperLeft and lowerRight.
Now that I have the structure declared, I need to put it to use. I first need to create an instance
of the structure. Here’s how that looks:
mailingListRecord record;
This statement allocates memory for the structure (120 bytes, give or take) and assigns that
memory to a variable named record. Now that I have an instance of the structure set up, I
can assign values to the data members:
strcpy(record.firstName, “Bruce”);
strcpy(record.lastName, “Reisdorph”);
strcpy(record.address, “123 Inspiration Pt.”);
strcpy(record.city, “Merced”);
strcpy(record.state, “CA”);
record.zip = 95031;
record.aFriend = true;
record.aFoe = false;
There is something you haven’t seen yet in this code. In order to access the data members of
a structure, you need to employ the structure member operator, which is a period placed
between the variable name and the data member. (If you forget to add the structure member
operator, you will probably have the compiler whining about undefined symbols.) The
structure member operator allows you to access a particular member of the structure—either
to read the value of the data member or to change the value of the data member.
If you want to, you can instantiate an object and supply its members all at one time:
mailingListRecord rec = {
“Bruce”,
“Reisdorph”,
“123 Inspiration Pt.”,
“Merced”,
“CA”,
95031,
true,
false
};
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