PHP Tutorial Tutorials - PHP Comparison Operators

PHP Comparison Operators

The comparison operators are used to compare two values.

Operator Name Example Result
== Equal $a == $b TRUE if $a is equal to $b.
=== Identical $a === $b TRUE if $a is equal to $b, and they are of the same type.
!= Not equal $a != $b TRUE if $a is not equal to $b.
<> Not equal $a <> $b TRUE if $a is not equal to $b.
!== Not identical $a !== $b TRUE if $a is not equal to $b, or they are not of the same type.
< Less than $a < $b TRUE if $a is strictly less than $b.
> Greater than $a > $b TRUE if $a is strictly greater than $b.
<= Less than or equal to $a <= $b TRUE if $a is less than or equal to $b.
>= Greater than or equal to $a >= $b TRUE if $a is greater than or equal to $b.
<=> Spaceship $a <=> $b -1,0,1 when $a is respectively less than, equal to, or greater than $b. Available as of PHP 7. 
<?php
$a = 12;
$b = 33;
$c = "12";
var_dump($a == $c);  // bool(true)
var_dump($a === $c); // bool(false)
var_dump($a != $b);  // bool(true)
var_dump($a <> $c);  // bool(false)
var_dump($a !== $c); // bool(true)
var_dump($a < $b);   // bool(true)
var_dump($a > $b);   // bool(false)
var_dump($a <= $b);  // bool(true)
var_dump($a >= $b);  // bool(false)

// Integers
echo 1 <=> 1; // 0
echo 1 <=> 2; // -1
echo 2 <=> 1; // 1
 
// Floats
echo 1.5 <=> 1.5; // 0
echo 1.5 <=> 2.5; // -1
echo 2.5 <=> 1.5; // 1
?>

PHP Comparison Tables

Comparisons of $x with PHP functions

gettype() empty() is_null() isset() boolean : if($x)
$x = ""; string TRUE FALSE TRUE FALSE
$x = null; NULL TRUE TRUE FALSE FALSE
var $x;(not assignment) NULL TRUE TRUE FALSE FALSE
$x is undefined NULL TRUE TRUE FALSE FALSE
$x = array(); array TRUE FALSE TRUE FALSE
$x = array('a', 'b'); array FALSE FALSE TRUE TRUE
$x = false; boolean TRUE FALSE TRUE FALSE
$x = true; boolean FALSE FALSE TRUE TRUE
$x = 21; integer FALSE FALSE TRUE TRUE
$x = 1; integer FALSE FALSE TRUE TRUE
$x = 0; integer TRUE FALSE TRUE FALSE
$x = -1; integer FALSE FALSE TRUE TRUE
$x = "21"; string FALSE FALSE TRUE TRUE
$x = "1"; string FALSE FALSE TRUE TRUE
$x = "0"; string TRUE FALSE TRUE FALSE
$x = "-1"; string FALSE FALSE TRUE TRUE
$x = "foo"; string FALSE FALSE TRUE TRUE
$x = "true"; string FALSE FALSE TRUE TRUE
$x = "false"; string FALSE FALSE TRUE TRUE

PHP Loose comparisons with ==

TRUE FALSE 1 0 -1 "1" "0" "-1" NULL array() "php" ""
TRUE TRUE FALSE TRUE FALSE TRUE TRUE FALSE TRUE FALSE FALSE TRUE FALSE
FALSE FALSE TRUE FALSE TRUE FALSE FALSE TRUE FALSE TRUE TRUE FALSE TRUE
1 TRUE FALSE TRUE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE
0 FALSE TRUE FALSE TRUE FALSE FALSE TRUE FALSE TRUE FALSE TRUE TRUE
-1 TRUE FALSE FALSE FALSE TRUE FALSE FALSE TRUE FALSE FALSE FALSE FALSE
"1" TRUE FALSE TRUE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE
"0" FALSE TRUE FALSE TRUE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE
"-1" TRUE FALSE FALSE FALSE TRUE FALSE FALSE TRUE FALSE FALSE FALSE FALSE
NULL FALSE TRUE FALSE TRUE FALSE FALSE FALSE FALSE TRUE TRUE FALSE TRUE
array() FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE TRUE TRUE FALSE FALSE
"php" TRUE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE
"" FALSE TRUE FALSE TRUE FALSE FALSE FALSE FALSE TRUE FALSE FALSE TRUE

PHP Strict comparisons with ===

TRUE FALSE 1 0 -1 "1" "0" "-1" NULL array() "php" ""
TRUE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
1 FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
0 FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
-1 FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
"1" FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE
"0" FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE
"-1" FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE
NULL FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE
array() FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE
"php" FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE
"" FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE
Date：2019-10-01 01:52:33 From:www.Lautturi.com author：Lautturi
PHP Bitwise Operators
PHP Logical Operators