!== Operator: It is called as non-identical operator. It returns true if operands are not equal, or they are not of the same type.
Syntax:
$x !== $y
Where $x and $y are the operands.
==! Operator: It is nothing but it can be further written as ==(!operand) which returns true or false depending on operands. Both the operators returns the boolean values either true or false.
Syntax:
$x ==! $y
Examples:
Input: $x = true
$y = false
Operator: $x !== $y
Output: true
Operator: $x ==! $y
Output: true
Example 1: This program uses both operands and returns the output.
<?php // PHP program to demonstrate // !== and ==! operator // Declare variables $x = true; $y = false; $z = true; // Using !== operator echo "Using !== operator\n"; // Is $x not equals to $y // so true returned var_dump($x !== $y); // Is $x not equals to $z // so false returned var_dump($x !== $z); // Is $y not equals to $z // so true returned var_dump($y !== $z); // Using ==! operator echo "\nUsing ==! operator\n"; // Is $x equals to (!$y) // so true returned var_dump($x ==! $y); // Is $x equals to (!$z) // so false returned var_dump($x ==! $z); // Is $y equals to (!$z) // so true returned var_dump($y ==! $z); ?> |
Output:
Using !== operator bool(true) bool(false) bool(true) Using ==! operator bool(true) bool(false) bool(true)
Program 2:
<?php // PHP program to demonstrate // !== and ==! operator // Dsclare associative array $x = array( "1" => "Geeks", "2" => "for", "3" => "Geeks"); $y = array( "5" => "Tony", "6" => "Captain", "7" => "Thor"); // Union of $x and $y $z = $x + $y; // Using !== operator echo "Using !== operator\n"; // Is $x not equals to $y // so true returned var_dump($x !== $y); // Is $x not equals to $z // so true returned var_dump($x !== $z); // Is $y not equals to $z // so true returned var_dump($y !== $z); // Using ==! operator echo "\nUsing ==! operator\n"; // Is $x equals to (!$y) // so false returned var_dump($x ==! $y); // Is $x equals to (!$z) // so false returned var_dump($x ==! $z); // Is $y equals to (!$z) // so false returned var_dump($y ==! $z); ?> |
Output:
Using !== operator bool(true) bool(true) bool(true) Using ==! operator bool(false) bool(false) bool(false)
