Data Protection in PHP
The reason to use classes is that they provide data protection; that is,
classes prevent a programmer from making logic errors in dealing with
complex data structures.
Using a class’s member functions to modify its
member variables protects a class’s data. By doing this, you are guaranteed
that all of the changes necessary to perform a desired task are executed
every time you want to perform the task.
For example, one desired function of a bank account class might be to keep a record for each transaction made with the account. However, if a programmer
simply modifies the account’s Balance member, he will probably
neglect to add an entry to the account history.
Good object-oriented programming practices dictate that a programmer
should use functions to access and modify the data within an object. Thus,
the programmer will have a smaller chance of making a mistake.
