Object Oriented Concept - Study Mode

[#116] Which keyword is used to access a static method or property from within the same class(rather than from child)?
Correct Answer

(C) self

Explanation

Solution: Self is to classes what the $this pseudo-variable is to objects.

[#117] In which of the following circumstance should you use a static reference to a non static method?
Correct Answer

(A) Making a method call using parent

Explanation

Solution: Making a method call using parent is the only circumstance in which you should use a static reference to a non-static method.

[#118] Which one of the following variable cannot be used inside a static method?
Correct Answer

(A) $this

Explanation

Solution: By definition, static methods are not invoked in the context of an object. For this reason, static methods and properties are often referred to as class variables and properties.

[#119] Which one of the following is the correct abstract method?
Correct Answer

(D) abstract public function write()

Explanation

Solution: An abstract method cannot have an implementation. You declare it in the normal way, but end the declaration with a semicolon rather than a method body.

[#120] What will be the output of the following PHP code? <?php class MyClass
{
}

$a = new MyClass

var_dump(!( $a instanceof stdClass ))

?>
Correct Answer

(A) bool(true)

Explanation

Solution: To check if an object is not an instanceof a class, the logical not operator can be used.