PHP Operators
PHP Operator is a symbol that performs specific operations on
operands.
In simple words, operators are used to performing operations on
variables or values. Operands are used to store or hold value.
Classification of operators (according to operands)
operators
can be categorized into four categories according to operands −
·
Unary prefix operators,
which use a single operand.
·
Binary operators,
which take two operands ex. Used in arithmetic
and logical operations.
·
The conditional operator (a
ternary operator), which takes three operands and evaluates either the
second or third expression, depending on the evaluation of the first
expression.
Classification of operators (according to functions)
1. Increment/Decrement Operators
2. Arithmetic operators
3. Assignment operators
4. Comparison operators
5. Logical operators
6. String operators
7. Array operators
8. Conditional assignment (or ternary) Operators
9. Spaceship Operators (Introduced in PHP 7)
10. Bitwise operator
1.
Increment/Decrement
Operators
These are called the unary operators as they
work on single operands. These are used to increment or decrement values.
|
OPERATOR |
NAME |
SYNTAX |
OPERATION |
|
++ |
Pre-Increment |
++$x |
First increments $x by one, then return $x |
|
— |
Pre-Decrement |
–$x |
First decrements $x by one, then return $x |
|
++ |
Post-Increment |
$x++ |
First returns $x, then increment it by one |
|
— |
Post-Decrement |
$x– |
First returns $x, then decrement it by one |
Example:
|
<?php $x = 2; echo ++$x, " Increments first then assign
\n"; echo $x, "\n"; $x = 2; echo $x++, " Assign first then increments
\n"; echo $x, "\n"; $x = 2; echo --$x, " Decrements first then Assign \n";
echo $x, "\n"; $x = 2; echo $x--, " Assign first then decrements
\n"; echo $x; ?> |
Output:
3 Increments first then assign
3
2 Assign first then increments
3
1 Decrements first then Assign
1
2 Assign first then decrements
1
=====================================================================
2.
PHP Arithmetic
Operators
The
PHP arithmetic operators are binary operators used with numeric values to
perform common arithmetical operations, such as addition, subtraction,
multiplication, etc.
|
Operator |
Name |
Example |
Result |
|
+ |
Addition |
$x
+ $y |
Sum
of $x and $y |
|
- |
Subtraction |
$x
- $y |
Difference
of $x and $y |
|
* |
Multiplication |
$x
* $y |
Product
of $x and $y |
|
/ |
Division |
$x
/ $y |
Quotient
of $x and $y |
|
% |
Modulus |
$x
% $y |
Remainder
of $x divided by $y |
|
** |
Exponentiation |
$x
** $y |
Result
of raising $x to the $y'th power |
Example:-
<html>
<head>
<title>Arithmetical Operators</title>
</head>
<body>
<?php
$a =
42;
$b =
20;
$c = $a + $b;
echo
"Addtion Operation Result: $c <br/>";
$c = $a - $b;
echo
"Substraction Operation Result: $c <br/>";
$c = $a * $b;
echo
"Multiplication Operation Result: $c <br/>";
$c = $a / $b;
echo
"Division Operation Result: $c <br/>";
$c = $a % $b;
echo
"Modulus Operation Result: $c <br/>";
$c = $a++;
echo
"Increment Operation Result: $c <br/>";
$c = $a--;
echo
"Decrement Operation Result: $c <br/>";
?>
</body>
</html>
Outputs −
Addition Operation Result: 62
Subtraction Operation Result: 22
Multiplication Operation Result: 840
Division Operation Result: 2.1
Modulus Operation Result: 2
Increment Operation Result: 42
Decrement Operation Result: 43
=====================================================================
3. PHP Assignment Operators (compound opt.)
The
PHP assignment operators are used with numeric values to write a value to a
variable.
The
basic assignment operator in PHP is "=". It means that the left
operand gets set to the value of the assignment expression on the right.
|
Assignment |
Same
as... |
Description |
|
x
= y |
x
= y |
The
left operand gets set to the value of the expression on the right |
|
x
+= y |
x
= x + y |
Addition |
|
x
-= y |
x
= x - y |
Subtraction |
|
x
*= y |
x
= x * y |
Multiplication |
|
x
/= y |
x
= x / y |
Division |
|
x
%= y |
x
= x % y |
Modulus |
EXAMPLE:-
<html>
<head>
<title>Assignment Operators</title>
</head>
<body>
<?php
$a =
42;
$b =
20;
$c =
$a + $b;
echo
"Addtion Operation Result: $c <br/>";
$c
+= $a;
echo
"Add AND Assigment Operation Result: $c <br/>";
$c
-= $a;
echo
"Subtract AND Assignment Operation Result: $c <br/>";
$c
*= $a;
echo "Multiply AND Assignment Operation
Result: $c <br/>";
$c
/= $a;
echo
"Division AND Assignment Operation Result: $c <br/>";
$c
%= $a;
echo
"Modulus AND Assignment Operation Result: $c <br/>";
?>
</body>
</html>
OUTPUT:-
Addtion Operation Result: 62
Add AND Assigment Operation Result: 104
Subtract AND Assignment Operation Result: 62
Multiply AND Assignment Operation Result: 2604
Division AND Assignment Operation Result: 62
Modulus AND Assignment Operation Result: 20
=====================================================================
4. PHP Comparison Operators
The
PHP comparison operators are used to compare two values (number or string):
|
Operator |
Name |
Example |
Result |
|
== |
Equal |
$x
== $y |
Returns
true if $x is equal to $y |
|
=== |
Identical |
$x
=== $y |
Returns
true if $x is equal to $y, and they are of the same type |
|
!= |
Not
equal |
$x
!= $y |
Returns
true if $x is not equal to $y |
|
<> |
Not
equal |
$x
<> $y |
Returns
true if $x is not equal to $y |
|
!== |
Not
identical |
$x
!== $y |
Returns
true if $x is not equal to $y, or they are not of the same type |
|
> |
Greater
than |
$x
> $y |
Returns
true if $x is greater than $y |
|
< |
Less
than |
$x
< $y |
Returns
true if $x is less than $y |
|
>= |
Greater
than or equal to |
$x
>= $y |
Returns
true if $x is greater than or equal to $y |
|
<= |
Less
than or equal to |
$x
<= $y |
Returns
true if $x is less than or equal to $y |
|
<=> |
Spaceship |
$x
<=> $y |
Returns
an integer less than, equal to, or greater than zero, depending on if $x is
less than, equal to, or greater than $y. Introduced in PHP 7. |
EXAMPLE:-
<html>
<head>
<title>Comparison Operators</title>
</head>
<body>
<?php
$a =
42;
$b =
20;
if(
$a == $b ) {
echo "TEST1 : a is equal to b<br/>";
}else {
echo "TEST1 : a is not equal to b<br/>";
}
if(
$a > $b ) {
echo "TEST2 : a is greater than
b<br/>";
}else {
echo "TEST2 : a is not greater than b<br/>";
}
if(
$a < $b ) {
echo "TEST3 : a is less than
b<br/>";
}else {
echo "TEST3 : a is not less than b<br/>";
}
if(
$a != $b ) {
echo "TEST4 : a is not equal to b<br/>";
}else {
echo "TEST4 : a is equal to b<br/>";
}
if(
$a >= $b ) {
echo "TEST5 : a is either greater than or equal to
b<br/>";
}else {
echo "TEST5 : a is neither greater
than nor equal to b<br/>";
}
if(
$a <= $b ) {
echo "TEST6 : a is either less than or equal to b<br/>";
}else {
echo "TEST6 : a is neither less than nor equal to
b<br/>";
}
?>
</body>
</html>
OUTPUT:-
TEST1 : a is not equal to b
TEST2 : a is greater than b
TEST3 : a is not less than b
TEST4 : a is not equal to b
TEST5 : a is either greater than or equal to b
TEST6 : a is neither less than nor equal to b
====================================================================
5.
Spaceship
Operators (Introduced in PHP 7)
PHP 7 introduced this operator called spaceship
operator (). These operators are used to compare values and return boolean
result, it returns integer values. If both the operands are equal, it returns
0. If the right operand is greater then it returns -1. If the left operand is
greater then it returns 1. The following table shows how it works in detail:
|
OPERATOR |
SYNTAX |
OPERATION |
|
$x < $y |
$x <=> $y |
Identical to -1 (right is greater) |
|
$x > $y |
$x <=> $y |
Identical to 1 (left is greater) |
|
$x <= $y |
$x <=> $y |
Identical to -1 (right is greater) or identical
to 0 (if both are equal) |
|
$x >= $y |
$x <=> $y |
Identical to 1 (if left is greater) or identical
to 0 (if both are equal) |
|
$x == $y |
$x <=> $y |
Identical to 0 (both are equal) |
|
$x != $y |
$x <=> $y |
Not Identical to 0 |
Example:
|
<?php $x = 50; $y = 50; $z = 25; echo $x <=> $y; echo "\n"; echo $x <=> $z; echo "\n"; echo $z <=> $y; echo "\n"; // We can do the same for Strings $x = "Ram"; $y = "Krishna"; echo $x <=> $y; echo "\n"; echo $x <=> $y; echo "\n"; echo $y <=> $x; ?> |
Output:
0
1
-1
1
1
-1
======================================================================
6. PHP Logical Operators
The
PHP logical operators are used to combine conditional statements.
|
Operator |
Name |
Example |
Result |
|
and |
And |
$x and $y |
True if both
$x and $y are true |
|
or |
Or |
$x or $y |
True if
either $x or $y is true |
|
xor |
Xor |
$x xor $y |
True if
either $x or $y is true, but not both |
|
&& |
And |
$x &&
$y |
True if both
$x and $y are true |
|
|| |
Or |
$x || $y |
True if
either $x or $y is true |
|
! |
Not |
!$x |
True if $x is
not true |
TRUTH
TABLE
|
VALUE 1 |
VALUE 2 |
AND |
OR |
XOR |
|
0 |
0 |
0 |
0 |
0 |
|
0 |
1 |
0 |
1 |
1 |
|
1 |
0 |
0 |
1 |
1 |
|
1 |
1 |
1 |
1 |
0 |
|
VALUES |
NOT |
|
0 |
1 |
|
1 |
0 |
EXAMPLE:-
<html>
<head>
<title>Logical Operators</title>
</head>
<body>
<?php
$a = 42;
$b = 0;
if( $a && $b ) {
echo "TEST1
: Both a and b are true<br/>";
}else{
echo "TEST1
: Either a or b is false<br/>";
}
if( $a and $b ) {
echo "TEST2
: Both a and b are true<br/>";
}else{
echo "TEST2
: Either a or b is false<br/>";
}
if( $a || $b ) {
echo "TEST3
: Either a or b is true<br/>";
}else{
echo "TEST3
: Both a and b are false<br/>";
}
if( $a or $b ) {
echo "TEST4
: Either a or b is true<br/>";
}else {
echo "TEST4
: Both a and b are false<br/>";
}
$a = 10;
$b = 20;
if( $a ) {
echo "TEST5
: a is true <br/>";
}else {
echo "TEST5
: a is false<br/>";
}
if( $b ) {
echo "TEST6
: b is true <br/>";
}else {
echo "TEST6
: b is false<br/>";
}
if( !$a ) {
echo "TEST7
: a is true <br/>";
}else {
echo "TEST7
: a is false<br/>";
}
if( !$b ) {
echo "TEST8
: b is true <br/>";
}else {
echo "TEST8
: b is false<br/>";
}
?>
</body>
</html>
OUTPUTS −
TEST1
: Either a or b is false
TEST2
: Either a or b is false
TEST3
: Either a or b is true
TEST4
: Either a or b is true
TEST5
: a is true
TEST6
: b is true
TEST7
: a is false
TEST8
: b is false
=====================================================================
7. PHP String Operators
PHP
has two operators that are specially designed for strings.
|
Operator |
Name |
Example |
Result |
|
. |
Concatenation |
$txt1
. $txt2 |
Concatenation
of $txt1 and $txt2 |
|
.= |
Concatenation
assignment |
$txt1
.= $txt2 |
Appends
$txt2 to $txt1 |
Example:-
<?php
$x
= "\r\nwelcome ";
$y
= "in ";
$z
= "sjkpgm!!! ";
echo
$x . $y . $z, "\r\n";
echo
nl2br("\n");
$x
.= $y . $z;
//echo $x . $y . $z;
echo
$x;
?>
Output:-
welcome in sjkpgm!!!
welcome in sjkpgm!!!
===================================================================
8. PHP Array Operators
The
PHP array operators are used to compare arrays.
|
Operator |
Name |
Example |
Result |
|
+ |
Union |
$x
+ $y |
Union
of $x and $y |
|
== |
Equality |
$x
== $y |
Returns
true if $x and $y have the same key/value pairs |
|
=== |
Identity |
$x
=== $y |
Returns
true if $x and $y have the same key/value pairs in the same order and of the
same types |
|
!= |
Inequality |
$x
!= $y |
Returns
true if $x is not equal to $y |
|
<> |
Inequality |
$x
<> $y |
Returns
true if $x is not equal to $y |
|
!== |
Non-identity |
$x
!== $y |
Returns
true if $x is not identical to $y |
Example:
|
<?php $x = array("k" => "Car",
"l" => "Bike"); $y = array("a" => "Train",
"b" => "Plane"); echo
nl2br("\n"); var_dump ($x + $y); echo
nl2br("\n"); var_dump($x == $y); echo
nl2br("\n"); var_dump($x != $y); echo
nl2br("\n"); var_dump($x <> $y); echo
nl2br("\n"); var_dump($x === $y); echo
nl2br("\n"); var_dump($x !== $y); ?> |
Output:
array(4) {
["k"]=>
string(3)
"Car"
["l"]=>
string(4)
"Bike"
["a"]=>
string(5)
"Train"
["b"]=>
string(5)
"Plane"
}
bool(false)
bool(true)
bool(true)
bool(false)
bool(true)
===================================================================
9.
Conditional
or Ternary Operators
These operators are used to compare two values and
take either of the results simultaneously, depending on whether the outcome is
TRUE or FALSE. it works as if…else statement.
Syntax:
$var = (condition)? value1 :
value2;
Here, the condition will either evaluate as true or
false. If the condition evaluates to True, then value1 will be assigned to the
variable $var otherwise value2 will be assigned to it.
|
OPERATOR |
NAME |
OPERATION |
|
?: |
Ternary |
If the condition is true? then $x : or else $y. This
means that if the condition is true then the left result of the colon is accepted
otherwise the result is on right. |
Example:
|
<?php $x = -12; echo ($x > 0) ? 'The number is
positive' : 'The number is negative'; ?> |
Output:
The number is negative.
EXAMPLE:-
<html>
<head>
<title>Arithmetical Operators</title>
</head>
<body>
<?php
$a =
10;
$b =
20;
/* If condition is true then assign a to result otheriwse b */
$result = ($a > $b ) ? $a : $b;
echo "TEST1 : Value of result is $result<br/>";
/* If condition is true then assign a to result otheriwse b */
$result = ($a < $b ) ? $a :$b;
echo "TEST2 : Value of result is $result<br/>";
?>
</body>
</html>
OUTPUT −
TEST1 : Value of result is 20
TEST2 : Value of result is 10
==================================================================
10.
Bitwise operator
The
Bitwise operators are used for bit-level operations on the operands. The
operators are first converted to bit-level and then the calculation is performed on
the operands.
The
mathematical operations such as addition, subtraction, multiplication, etc. can
be performed at bit-level for faster processing.
Bitwise
operators are :-
Description
|
Operator |
Name |
Example |
Result |
|
& |
And |
$x & $y |
Bits that are set in both $x and $y are set. |
|
| |
Or |
$x | $y |
Bits that are set in either $x or $y are set. |
|
^ |
Xor |
$x ^ $y |
Bits that are set in $x or $y but not both are set. |
|
~ |
Not |
~$x |
Bits that are set in $x are not set, and vice versa. |
|
<< |
Shift left |
$x << $y |
Shift the bits of $x $y steps to the left.# |
|
>> |
Shift right |
$x >> $y |
Shift the bits of $x $y steps to the right.* |
Concept of bit:-
A bit (Binary digit) is the basic unit
of information stored in two states, as ON or OFF.
ON state represented by 1 and OFF state
represented by 0. these digits are used by BINARY number
system which base of 2.
In decimal number system, a number construct upon the base of 10.
Conversion to decimal from binary number -
1011010=(1 x 26)+(0 x 25)+(1 x 24)+(1 x
23)+(0 x 22)+(1 x 21)+(0 x 20)
=(1 x 64) +(0 x
32)+(1 x 16)+(1 x 8)+(0 x 4)+(1 x 2)+(0 x 1)
=64+0+16+8+0+2+0
=90
So, (1011010)2= (90)10
------------------------------------------------------------------------------------------------------------
Byte
A byte is a sequence of eight bits. The maximum value of a byte is 255.
Table show of a byte:-
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
|
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
|
|
|
|
27 |
26 |
25 |
24 |
23 |
22 |
21 |
20 |
|
|
|
|
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
= |
255 |
A decimal number 93 can be represented in binary form
like bellow –
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
|
0 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
|
|
|
|
27 |
26 |
25 |
24 |
23 |
22 |
21 |
20 |
|
|
|
|
0 |
64 |
0 |
16 |
8 |
4 |
0 |
1 |
= |
93 |
-----------------------------------------------------------------------------------------------------------
Bitwise AND (&)
According to the truth table:-
TRUTH
TABLE
|
VALUE
1 |
VALUE
2 |
AND |
|
0 |
0 |
0 |
|
0 |
1 |
0 |
|
1 |
0 |
0 |
|
1 |
1 |
1 |
Example of PHP bitwise AND with one shared bit
<?php
$x=13;
$y=22;
echo $x & $y;
?>
Output of the example
4
Explanation
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
$x |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
1 |
= |
13 |
|
$y |
0 |
0 |
0 |
1 |
0 |
1 |
1 |
0 |
= |
22 |
|
$x & $y |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
= |
04 |
Bitwise OR ( | )
According to the truth table
TRUTH
TABLE
|
VALUE
1 |
VALUE
2 |
OR |
|
0 |
0 |
0 |
|
0 |
1 |
1 |
|
1 |
0 |
1 |
|
1 |
1 |
1 |
Example of PHP bitwise OR
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
$x |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
= |
5 |
|
$y |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
1 |
= |
11 |
|
$x & $y |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
1 |
= |
15 |
<?php
$x=5;
$y=11;
echo $x | $y;
?>
Output
15
Explanation
Bitwise XOR (^)
The Xor operator also performs a bitwise comparison in two numeric expressions
and sets the corresponding bit in the result. When one and only one of the expressions
evaluates to true the result is true.
TRUTH
TABLE
|
VALUE
1 |
VALUE
2 |
XOR |
|
0 |
0 |
0 |
|
0 |
1 |
1 |
|
1 |
0 |
1 |
|
1 |
1 |
0 |
The below table shows how a XOR operation performs.
|
Expression1 |
Expression2 |
Result |
|
False |
False |
False |
|
False |
True |
True |
|
True |
False |
True |
|
True |
True |
False |
Example of PHP bitwise XOR
<?php
$x=12;
$y=11;
echo $x ^ $y;
?>
Output
7
Explanation
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
$x |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
= |
12 |
|
$y |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
1 |
= |
11 |
|
$x ^ $y |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
= |
07 |
Bitwise NOT
The below table will display how NOT operator performs on $x and $y and
returns true when a set bit of one expression is not set in another expression.
Example of PHP bitwise NOT using after AND
<?php
$x=12;
$y=10;
echo $x & ~ $y;
?>
Output
4
Explanation
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
$x |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
= |
12 |
|
$y |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
= |
10 |
|
~$y |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
= |
05 |
|
$x & ~$y |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
= |
04 |
Example of PHP bitwise NOT using before AND<?php
$x=12;
$y=10;
echo ~ $x & $y;
?>
Output
2
Bit Shifting
If a and b are two numbers, BIT SHIFTING shifts a bits b number of
steps. each step refers to multiply by two if it is BIT SHIFT LEFT. If it is
BIT SHIFT RIGHT, then each step refers to division by two.
Example of PHP Bit Shifting ( left shift )<?php
$x=8;
$y=3;
echo $x << $y;
?>
Output
64
Explanation
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
$x |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
= |
8 |
|
Output |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
= |
64 |
In this example, the value of $x
that is 8 is taken and a BIT SHIFT LEFT operation is performed. So, 8 is
multiplied by 2 thrice. Thus we get 8 x 2 x 2 x 2 = 64.
Example of PHP Bit Shifting ( right shift )
<?php
$x=8;
$y=3;
echo $x >> $y;
?>
Output
1
Explanation
|
1 Byte ( 8 bits ) |
||||||||||
|
Place Value |
128 |
64 |
32 |
16 |
8 |
4 |
2 |
1 |
|
|
|
$x |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
= |
8 |
|
Output |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
= |
1 |
In the above example, a value of $x that is 8 is taken and a BIT SHIFT
RIGHT operation is performed. So, 8 is divided by 2 three times. Thus we get
8/2=4/2=2/2 = 1.
Example:-
|
<?php
//
PHP code to demonstrate Bitwise Operator. //
Bitwise AND $First
= 5; $second
= 3; $answer
= $First & $second; print_r("Bitwise
& of 5 and 3 is $answer"); print_r("\n");
//
Bitwise OR $answer
= $First | $second; print_r("Bitwise
| of 5 and 3 is $answer"); print_r("\n");
//
Bitwise XOR $answer
= $First ^ $second; print_r("Bitwise
^ of 5 and 3 is $answer"); print_r("\n");
//
Bitwise NOT $answer
= ~$First; print_r("Bitwise
~ of 5 is $answer"); print_r("\n");
//
Bitwise Left shift $second
= 1; $answer
= $First << $second; print_r("5
<< 1 will be $answer"); print_r("\n");
//
Bitwise Right shift $answer
= $First >> $second; print_r("5
>> 1 will be $answer"); print_r("\n");
?>
|
Output:
Bitwise & of 5
and 3 is 1
Bitwise | of 5 and
3 is 7
Bitwise ^ of 5 and
3 is 6
Bitwise ~ of 5 is
-6
5 << 1 will
be 10
5 >> 1 will
be 2
==================================================================
Precedence of PHP Operators
the highest precedence appears at the top of the
table, those with the lowest appear at the bottom. Within an expression, higher
precedence operators will be evaluated first.
|
Category |
Operator |
Associativity |
|
Unary |
! ++ -- |
Right to left |
|
Multiplicative |
* / % |
Left to right |
|
Additive |
+ - |
Left to right |
|
Relational |
< <= > >= |
Left to right |
|
Equality |
== != |
Left to right |
|
Logical AND |
&& |
Left to right |
|
Logical OR |
|| |
Left to right |
|
Conditional |
?: |
Right to left |
|
Assignment |
= += -= *= /= %= |
Right to left |
======================================================================
Type Operators
The
type operator instanceof is used to determine whether an object,
its parent, and its derived class are the same type or not. Basically, this
operator determines which certain class the object belongs to. It is used in
object-oriented programming.
<?php
//class declaration
class Developer
{}
class Programmer
{}
//creating an object of type Developer
$charu = new Developer();
//testing the type of object
if( $charu instanceof Developer)
{
echo "Charu is a developer.";
}
else
{
echo "Charu is a programmer.";
}
echo "</br>";
var_dump($charu instanceof Developer); //It will return true.
var_dump($charu instanceof Programmer); //It will return false.
?>
Output:
Charu
is a developer.
bool(true)
bool(false)
======================================================================
Error Control Operators
PHP
has one error control operator, i.e., at (@) symbol.
Whenever it is used with an expression, any error message will be ignored or hidden
that might be generated by that expression.
|
Operator |
Name |
Example |
Explanation |
|
@ |
at |
@file
('non_existent_file') |
Intentional
file error |
=============================
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