PHP operators

I will start with you by the list of operators type :

* Assignment Operators
* Arithmetic Operators
* Comparison Operators
* String Operators
* Combination Arithmetic & Assignment Operators

1- Assignment Operators

This is done using "="
For example

Code:

   <?
        $x=5;
        $y=$x;
         
    ?>


now both x , and y have the value 5

2 - Arithmetic Operators


Operator English Example

Code:

   
    +  Addition            1 + 2
     -    Subtraction           4 - 2
     *  Multiplication            2 * 2
    /     Division              20 / 4
    %  Modulus                  7 % 3

Code:

<?php 
$addition = 1 + 2; 
$subtraction = 4 - 2; 
$multiplication = 2 * 2; 
$division = 20 / 4; 
$modulus = 7 % 3; 
echo "addition: 1 + 2= ".$addition."<br />"; 
echo "subtraction: 4 - 2 = ".$subtraction."<br />"; 
echo "multiplication:  2* 2 = ".$multiplication."<br />"; 
echo "division: 20 / 4 = ".$division."<br />"; 
echo "modulus: 7 % 3 = " . $modulus ;
   

the output is :

Code:

addition: 1+ 2 = 3
subtraction: 4 - 2 = 2
multiplication: 2 * 2 = 4
division: 20 / 4 = 5
modulus: 7 % 3 = 1


3- Comparison Operators

Operator English Example Result
== Equal To $x == $y false
!= Not Equal To $x != $y true
< Less Than $x < $y true
> Greater Than $x > $y false
<= Less Than or Equal To $x <= $y true
>= Greater Than or Equal To $x >= $y false


4. String Operators

The dot (.) Operator between two strings as we saw before . like :

Code:

   $mstring1="Welcome to ";
   $mstring2="Codemiles Forums";
    echo $mstring1.$mstring2;


the output is :

Code:

Welcome to Codemiles Forums


5- Combination Arithmetic & Assignment Operators


If you want to increase a variable by some value . you can do the follow :
$x=$x+1;

or using short hand :
$x+=1;

here all some examples

Code:

Operator   English    Example    Equivalent Operation
+=          Plus Equals     $x += 1;    $x = $x + 1;
-=           Minus Equals     $x -= 1;    $x = $x - 1;
*=          Multiply Equals    $x *= 1;    $x = $x * 1;
/=           Divide Equals    $x /= 1;    $x = $x / 1;
%=         Modulo Equals    $x %= 1;    $x = $x % 1;
.=              Concatenate Equals    $my_str.="codemiles";    $my_str = $my_str . "codemiles";

before i close this topic i will talk about some thing which is . how to do pre/post increment and decrement . It is more shorter for adding or subtracting 1 from a variable.

$x++ is equal to $x+=1 or $x=$x+1
$x-- is equal to $x-=1 or $x=$x-1

Is $x++ different from $++x in your code ? Yes

you specify the increment before or after the line of code is executed
Example

Code:

$value=10;
  echo "my value is ".$x++;
echo "my value is ".$x;
$value=10;
  echo "<br/>my value is ".$++x;
echo "my value is ".$x;



the output is :

Code:

my value is 10 my value is 11
my value is 11 my value is 11


i wish it is clear

thanks