When using OOP in PHP I've seen a lot of functions written like this: function __myfunc(){}
I want to know what the underscores do. I've read they protect the function but from what and how?
Another example:
class myClass{
function __myFunc(){
return ' what am i doing?';
}
}
$question = new myClass;
echo $question->__myFunc();
The underscores have no effect. However, two underscores are used to indicate a magic function that has special meaning, e.g. the constructor __construct() or the destructor __destruct(). Some people used one or two underscores to indicate that a method is meant to be "private", i.e. used only internally. Since this feature is implemented in PHP >= 5 as a special keyword, you shouldn't use this "underscoring" anymore:
class myClass{
private function myFunc() {
return ' what am i doing?';
}
}
$question = new myClass();
echo $question->myFunc(); // fails!
This is basically a code notation that this method is private and the user of the code should not play with it. (critical to the overall functionality)
You should place an underscore symbol only on a private methods, it is considered a good practice.
There are some of the functions which are called magic others are just the notation to mark them as private - so if someone form your team see this function with underscore he will think of it as private. But actually you can use them outside of class itself. To protect methods inside class you need to use access modifiers
