I am a new programmer, and I started in C and am now starting to enjoy JavaScript and a tiny bit of PHP more. Lately I've heard the terms 'private' and 'public' functions a lot. Could anybody give an explanation of the both and how they are of use to a programmer?
And I'm probably totally wrong here... but is a
(function(){})
in javascript a private function?
public members can be accessed from outside the class they were declared in, private members can only be accessed from within the class they were declared in. Private members are commonly manipulated through get/set methods, which allows for greater encapsulation and hides the implementation from the calling function.
We use these keywords to specify access levels for member variables, or for member functions (methods). Public variables, are variables that are visible to all classes. Private variables, are variables that are visible only to the class to which they belong. Protected variables, are variables that are visible only to the class to which they belong, and any subclasses. Deciding when to use private, protected, or public variables is sometimes tricky. You need to think whether or not an external object (or program), actually needs direct access to the information. If you do want other objects to access internal data, but wish to control it, you would make it either private or protected, but provide functions which can manipulate the data in a controlled way