- An operator is a special symbol that tells the compiler to perform some task.
PHP offers various operators to perform different tasks.
We can divide them into the following categories based on their operations.
- Arithmetic Operators
- Assignment Operators
- Incrementing/Decrementing Operators
- Relational Operators
- Logical Operators
- Array Operators
- Concatenate operator
Arithmetic Operators
Arithmetic operators are used to perform arithmetic tasks such as addition, subtraction, division etc. Main operators in this category are as follow:
Operator | Name | Description | Example | Result |
x + y | Addition | Sum of x and y | 2 + 2 | 4 |
x – y | Subtraction | Difference of x and y | 5 – 2 | 3 |
x * y | Multiplication | Product of x and y | 5 * 2 | 10 |
x / y | Division | Quotient of x and y | 15 / 5 | 3 |
x % y | Modulus | Remainder of x divided by y | 5 % 2 10 % 8 10 % 2 |
1 2 0 |
– x | Negation | Opposite of x | – 2 | |
a . b | Concatenation | Concatenate two strings | “Hi” . “Ha” | HiHa |
Assignment Operators
- Assignment operator is used to assign righ hand side value to left hand side variable.
- In PHP “=” is used as assignment operator. It means that the left operand gets the value of the expression on the right hand side.
- For example the following code will assign the value 10 to variable x
$x = 10 ;
- Some various forms of assignment are as follow:
Assignment | Remark | 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 |
Incrementing/Decrementing Operators
- Increment and decrement operator adds and subtracts to and from the current value by 1 respectively.
- Basic increment and decrement operators are “++” and “ –“.
- It has two forms: prefix and postfix.
Operator | Name | Description |
++ x | Prefix | Increments x by one, then returns x |
x ++ | Postfix | Returns x, then increments x by one |
— x | Prefix | Decrements x by one, then returns x |
x — | Postfix | Returns x, then decrements x by one |
Relational Operators
- Relational operators are used to compare two values.
- Some examples are as follow:
Operator | Name | Description | Example |
x == y | Equal | True if x is equal to y | 5==8 returns false |
x === y | Identical | True if x is equal to y, and they are of same type | 5===”5″ returns false |
x != y | Not equal | True if x is not equal to y | 5!=8 returns true |
x <> y | Not equal | True if x is not equal to y | 5<>8 returns true |
x !== y | Not identical | True if x is not equal to y, or they are not of same type | 5!==”5″ returns true |
x > y | Greater than | True if x is greater than y | 5>8 returns false |
x < y | Less than | True if x is less than y | 5<8 returns true |
x >= y | Greater than or equal to | True if x is greater than or equal to y | 5>=8 returns false |
x <= y | Less than or equal to | True if x is less than or equal to y | 5<=8 returns true |
Logical Operators
- Logical operators are used to perform logical task.
Operator | Name | Description | Example |
x and y | And | True if both x and y are true | x=6 y=3 (x < 10 and y > 1) returns true |
x or y | Or | True if either or both x and y are true | x=6 y=3 (x==6 or y==5) returns true |
x xor y | Xor | True if either x or y is true, but not both | x=6 y=3 (x==6 xor y==3) returns false |
x && y | And | True if both x and y are true | x=6 y=3 (x < 10 && y > 1) returns true |
x || y | Or | True if either or both x and y are true | x=6 y=3 (x==5 || y==5) returns false |
! x | Not | True if x is not true | x=6 y=3 !(x==y) returns true |
Array Operators
- Array operators are used to manipulate and perform different operations on array such as joining, equality check etc.
- Some examples are as follow:
Operator | Name | Description |
x + y | Union | Union of x and y |
x == y | Equality | True if x and y have the same key/value pairs |
x === y | Identity | True if x and y have the same key/value pairs in the same order and of the same types |
x != y | Inequality | True if x is not equal to y |
x <> y | Inequality | True if x is not equal to y |
x !== y | Non-identity | True if x is not identical to y |
Concatenate Operator
In PHP we can use period (“.”) operator as a concatenate operator to join two strings.
For example:
$str1 = "Hello" ;
$str2 = "Welcome!" ;
echo $str2 . $str1 ;
- The above code will display “Hello Welcome!” by joining two strings str1 and str2.