Overview
The operator is a symbol that is used to execute operations on operands.
PHP divides the operators into the following groups:
- Arithmetic Operators
- Assignment Operators
- Bitwise Operators
- Comparison Operators
- Incrementing/Decrementing Operators
- Logical Operators
- String Operators
- Type Operators
- Error Control Operators
Arithmetic Operators
Arithmetic operators are used to performing common arithmetic operations such as addition, subtraction, etc. with numeric values.
| Operator | Name | Example | Explanation |
|---|---|---|---|
| + | Addition | $a + $b | Sum of $a and $b |
| - | Subtraction | $a - $b | A difference of $a and $b |
| * | Multiplication | $a * $b | Product of $a and $b |
| / | Division | $a / $b | Quotient of $a and $b |
| % | Modulus | $a % $b | The remainder of $a divided by $b |
| ** | Exponentiation | $a ** $b | Result of raising $a to the $b'th power |
Assignment Operators
| Operator | Name | Example | Explanation |
|---|---|---|---|
| = | Assign | $a = $b | The value of the right operand is assigned to the left operand. |
| += | Add then Assign | $a += $b | Addition same as $a = $a + $b |
| -= | Subtract then Assign | $a -= $b | Subtraction same as $a = $a - $b |
| *= | Multiply then Assign | $a *= $b | Multiplication same as $a = $a * $b |
| /= | Divide then Assign (quotient) | $a /= $b | Find quotient same as $a = $a / $b |
| %= | Divide then Assign (remainder) | $a %= $b | Find remainder same as $a = $a % $b |
Bitwise Operators
The bitwise operators are used to perform bit-level operations on variables.
| Operator | Name | Example | Explanation |
|---|---|---|---|
| & | And | $a & $b | Bits that are 1 in both $a and $b are set to 1, otherwise 0. |
| | | Or (Inclusive or) | $a | $b | Bits that are 1 in either $a or $b are set to 1 |
| ^ | Xor (Exclusive or) | $a ^ $b | Bits that are 1 in either $a or $b are set to 0. |
| ~ | Not | ~$a | Bits that are 1 set to 0 and bits that are 0 are set to 1 |
Comparison Operators
Comparison operators used to compare two values, such as number or string.
| Operator | Name | Example | Explanation |
|---|---|---|---|
| == | Equal | $a == $b | Return TRUE if $a is equal to $b |
| === | Identical | $a === $b | Return TRUE if $a is equal to $b, and they are of same data type |
| !== | Not identical | $a !== $b | Return TRUE if $a is not equal to $b, and they are not of same data type |
| != | Not equal | $a != $b | Return TRUE if $a is not equal to $b |
| <> | Not equal | $a <> $b | Return TRUE if $a is not equal to $b |
| < | Less than | $a < $b | Return TRUE if $a is less than $b |
| > | Greater than | $a > $b | Return TRUE if $a is greater than $b |
| <= | Less than or equal to | $a <= $b | Return TRUE if $a is less than or equal $b |
| >= | Greater than or equal to | $a >= $b | Return TRUE if $a is greater than or equal $b |
| <=> | Spaceship | $a <=>$b | Return -1 if $a is less than $b Return 0 if $a is equal $b Return 1 if $a is greater than $b |
Incrementing/Decrementing Operators
The increment and decrement operators are used to increase and decrease the value of a variable.
| Operator | Name | Example | Explanation |
|---|---|---|---|
| ++ | Increment | ++$a | Increment the value of $a by one, then return $a |
| $a++ | Return $a, then increment the value of $a by one | ||
| -- | decrement | --$a | Decrement the value of $a by one, then return $a |
| $a-- | Return $a, then decrement the value of $a by one |
Logical Operators
The logical operators are used to perform bit-level operations on variables.
| Operator | Name | Example | Explanation |
|---|---|---|---|
| and | And | $a and $b | Return TRUE if both $a and $b are true |
| or | Or | $a or $b | Return TRUE if either $a or $b is true |
| xor | Xor | $a xor $b | Return TRUE if either $ or $b is true but not both |
| ! | Not | ! $a | Return TRUE if $a is not true |
| && | And | $a && $b | Return TRUE if either $a and $b are true |
| || | Or | $a || $b | Return TRUE if either $a or $b is true |
String Operators
The string operators are used to operate on strings.
| Operator | Name | Example | Explanation |
|---|---|---|---|
| . | Concatenation | $a . $b | Concatenate both $a and $b |
| .= | Concatenation and Assignment | $a .= $b | First concatenate $a and $b, then assign the concatenated string to $a, e.g. $a = $a . $b |
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 that might be generated by that expression.
| Operator | Name | Example | Explanation |
|---|---|---|---|
| @ | at | @file ('non_existent_file') | Intentional file error |