PHP Operators

• Arithmetic Operators
• Assignment Operators
• Bitwise Operators
• Comparison Operators
• Error Control Operators
• Execution Operators
• Incrementing/Decrementing Operators
• Logical Operators
• String Operators
• Array Operators
• Type Operators

PHP Arithmetic Operators

Please check the following Operators with $a=10 , $b=4

Operator	Example	Result	Name	Description
+	$a + $b	14	Addition	Sum of $a and $b
-	$a - $b	4	Subtraction	Difference of $a and $b
*	$a * $b	40	Multiplication	Product of $a and $b
/	$a / $b	2.5	Division	Quotient of $a and $b
%	$a % $b	2	Modulo	Remainder of $a divided by $b
**	$a ** $b	10000	Exponentiation	Result of raising $a to the $b'th power
+	+$a	10	Identity	Conversion of $a to int or float
-	-$a	-10	Negation	Opposite of $a

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PHP Assignment Operators

The PHP assignment operator is "+". In assignment operator value is assigned like $a=10 , $b=4.

Example	Same As	Result	Description
$a = $b	$a = $b	4	The left operand get the value of right operand
$a += $b	$a = $a + $b	14	Addition
$a -= $b	$a = $a - $b	6	Subtraction
$a *= $b	$a = $a * $b	40	Multiplication
$a /= $b	$a = $a / $b	2.5	Division
$a %= $b	$a = $a % $b	2	Modulus

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PHP Bitwise Operators

Result with $a=10 , $b=4.

Operator	Example	Result	Name	Description
&	$a & $b	0	And	Bits that are set in both $a and $b are set
|	$a | $b	14	Or	Bits that are set in either $a or $b are set.
^	a ^ b	14	Xor	Bits that are set in $a or $b but not both are set
~	~ $a	-11	Not	Bits that are set in $a are not set, and vice versa
<<	$a << $b	160	Shift left	Shift the bits of $a $b steps to the left
<<	$a >> $b	0	Shift right	Shift the bits of $a $b steps to the right

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PHP Comparison Operators

Operator	Example	Name	Description
==	X == Y	Equal	TRUE if X is equal to Y
===	X === Y	Identical	TRUE if X is equal to Y, and they are of the same data type(int,string,float,array,object etc)
!=	X != Y	Not equal	TRUE if X is not equal to Y after type juggling.
<>	X <> Y	Not equal	TRUE if X is not equal to Y after type juggling.
!==	X !== Y	Not identical	TRUE if X is not equal to Y, or they are not of the same data type(int,string,float,array,object etc).
<	X < Y	Less than	TRUE if X is strictly less than Y.
>	X > Y	Greater than	TRUE if X is strictly greater than Y.
<=	X <= Y	Less than or equal to	TRUE if X is less than or equal to Y.
>=	X >= Y	Greater than or equal to	TRUE if X is greater than or equal to Y.
<=>	X <=> Y	Spaceship	TRUE An integer less than, equal to, or greater than zero when $a is less than, equal to, or greater than $b, respectively.

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PHP Error Control Operators

The sign of error control operator is (@), it's used to hide the error messages that might be generated by that expression

Example 1

echo $string; 
Output:: it shows Notice:Undefined variable

Example 2

echo @$string; 
Output::It does not show any such type of "Notice"

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PHP Execution Operators

The sign of execution operator is backticks (``), it's used to execute as a shell command

Example 1

$website = 'www.example.com';
echo `ping -n 5 {$website}`;

Example 2

echo @$string; 
Output::It does not show any type of "Notice"

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PHP Incrementing/Decrementing Operators

PHP Incrementing/Decrementing operators are used to increment/decrement a variable's value.

Result with $a=5; $b=10; $c=20; $d=25;.

Operator	Result	Name	Description
++$a	6	Pre-increment	Increments $a by one, then returns $a.
$b++	10	Post-increment	Returns $b, then increments $a by one.
--$c	19	Pre-decrement	Decrements $c by one, then returns $c.
$d--	25	Post-decrement	Returns $d, then decrements $d by one.

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PHP Logical Operators

Operator	Example	Name	Description
and	$a and $b	And	TRUE if both $a and $b are TRUE
or	$a or $b	Or	TRUE if either $a or $b is TRUE
xor	$a xor $b	Xor	TRUE if either $a or $b is TRUE, but not both.
!	! $a	Not	TRUE if $a is not TRUE
&&	$a && $b	And	TRUE if both $a and $b are TRUE
||	$a || $b	Or	TRUE if either $a or $b is TRUE

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PHP String Operators

PHP has two String operators only, first is the concatenation operator ('.') and second is the concatenating assignment operator ('.=')

Example 1 - PHP concatenation operator ('.')

$string1 = "testing";
$string2 = "I am ".$string1;
echo $string2;
//Output :: I am testing

Example 2 - PHP concatenating assignment operator ('.=')

$string1 = "I am";
$string1 .= " testing";
echo $string1;
//Output :: I am testing

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PHP Array Operators

Operator	Example	Name	Description
+	$a + $b	Union	Union of $a and $b
==	$a == $b	Equality	TRUE if $a and $b have the same key/value pairs.
===	$a === $b	Identity	TRUE if $a and $b have the same key/value pairs in the same order and of the same types.
!=	$a != $b	Inequality	TRUE if $a is not equal to $b
<>	$a <> $b	Inequality	TRUE if $a is not equal to $b
!==	$a |== $b	Non-identity	TRUE if $a is not identical to $b

$a = array("a" => "PHP", "c" => "JS");
$b = array("a" => "HTML", "b" => "CSS", "d" => "Python");
$c = $a + $b; // Union of $a and $b
var_dump($c);

//Output ::
array (size=4)
  'a' => string 'PHP' (length=3)
  'c' => string 'JS' (length=2)
  'b' => string 'CSS' (length=3)
  'd' => string 'Python' (length=6)

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PHP Type Operators

Example 1 - PHP instanceof operator with classes

class classA 
{
}
class classB 
{
}
$a = new classA;
var_dump($a instanceof classA); // true
var_dump($a instanceof classB); // false

Example 2 - PHP instanceof operator with inherited classes

class classA 
{ 
}
class classB extends classA
{
}
$a = new classB;
var_dump($a instanceof classA); // true
var_dump($a instanceof classB); // true

Example 3 - PHP instanceof operator with interfaces

interface interfaceA
{ 
}
class classB implements interfaceA
{	
}
$a = new classB;
var_dump($a instanceof classB); // true
var_dump($a instanceof interfaceA); // true

Example 4 - PHP instanceof with other variables

interface interfaceA
{
}
class classB implements interfaceA
{
}
$a = new classB;
$b = new classB;
$c = 'classB';
$d = 'NotClass';
var_dump($a instanceof $a); // true
var_dump($a instanceof $b); // true
var_dump($a instanceof $c); // true
var_dump($a instanceof $d); // false