Operators have the form of symbols (such as + and -) and combinations of symbols (such as ++ and +=).
Arithmetic operators:
The Arithmetic operators are:
| Operator | Description |
|---|---|
| + | Addition |
| - | Subtraction |
| * | Multiplication |
| / | Division |
| % | Modulus (division remainder) |
| ++ | Increment |
| -- | Decrement |
PHP Code & examples:
<?php
$var1 = 25 + 5 ; // returns 30
$var2 = $var1 / 5 ; // returns 6
$var3 = $var1 + $var2 ; // returns 36
?>
$var1 = 25 + 5 ; // returns 30
$var2 = $var1 / 5 ; // returns 6
$var3 = $var1 + $var2 ; // returns 36
?>
Assignment operators:
The Assignment operators are used to facilitate assigning values to variables:
| Operator | Description |
|---|---|
| += | Addition and Assignment |
| -= | Subtraction and Assignment |
| *= | Multiplication and Assignment |
| /= | Division and Assignment |
| % | Modulo and Assignment |
| .= | Concatenation and Assignment |
PHP Code & examples:
<?php
$var = 20 ;
$var = $var + 5 ; // returns 25
// We can use the addition and assignment
$var += 5 ; // returns 25
//these two methods return the same result, but as you see, the second is shorter and better !
?>
$var = 20 ;
$var = $var + 5 ; // returns 25
// We can use the addition and assignment
$var += 5 ; // returns 25
//these two methods return the same result, but as you see, the second is shorter and better !
?>
Comparison Operators:
The Comparison Operators returns a value true or false after comparing two values:
| Operator | Description |
|---|---|
| == | is equal to |
| != | is not equal |
| > | is greater than |
| < | is less than |
| >= | is greater than or equal ro |
| <= | is less than or equal to |
the comparaison operators are the most of time used in conditions:
<?php
$var = 20 ;
if ($var1==$var2)
// this instruction will be executed only if $var1 is equal to $var2
if ($var1!=$var2)
// this instruction will be executed only if $var1 is not equal to $var2
if ($var1<$var2)
// this instruction will be executed only if $var1 is less than $var2
// and this is also possible:
$var = ($var1==$var2);
?>
$var = 20 ;
if ($var1==$var2)
// this instruction will be executed only if $var1 is equal to $var2
if ($var1!=$var2)
// this instruction will be executed only if $var1 is not equal to $var2
if ($var1<$var2)
// this instruction will be executed only if $var1 is less than $var2
// and this is also possible:
$var = ($var1==$var2);
?>
Logical Operators:
The logical Operators are used in conditions, they make a relation between two or more condition. Logical operations are also know as Boolean operators:
| Operator | Description |
|---|---|
| && | And: returns true only if two operands (conditions/expressions) are trues |
| || | Or: returns true if at least one of the two operands returns true |
| ! | Not: if the operand is true, returns false, else returns true |
| xor | Xor: returns true if only one of the operands returns true. If the two operands are true, it returns false. |
Increment and decrement Operators:
The logical Operators are used in conditions, they make a relation between two or more condition. Logical operations are also know as Boolean operators:
| Operator | Description |
|---|---|
| ++$var | Increments the variable value before it is used in rest of expression |
| --$var | Decrements the variable value before it is used in rest of expression |
| $var++ | Increments the variable value after it is used in rest of expression |
| $var-- | Decrements the variable value after it is used in rest of expression |
