PHP operators are symbols used to perform different types of operations on variables, values, and expressions. Here are the different types of PHP operators:

- Arithmetic operators
- Assignment operators
- Comparison operators
- Increment/Decrement operators
- Logical operators
- String operators
- Array operators
- Conditional assignment operators

### 1. PHP Arithmetic Operators

Arithmetic operators are used to perform mathematical operations. The arithmetic operators are:

Operator | Name | Example | Result |

+ | Addition | $x + $y | Sum of $x & $y |

– | Substraction | $x – $y | Difference of $x & $y |

* | Multiplication | $x * $y | Product of $x & $y |

/ | Division | $x / $y | Quotient of $x & $y |

% | Modulus | $x % $y | Remainder of $x divided by $y |

**Here are some examples of arithmetic operators in PHP:**

<?php $a = 10; $b = 5; // Addition $c = $a + $b; echo "Addition: " . $c . "<br>"; // Subtraction $c = $a - $b; echo "Subtraction: " . $c . "<br>"; // Multiplication $c = $a * $b; echo "Multiplication: " . $c . "<br>"; // Division $c = $a / $b; echo "Division: " . $c . "<br>"; // Modulus $c = $a % $b; echo "Modulus: " . $c . "<br>"; // Exponentiation $c = $a ** $b; echo "Exponentiation: " . $c . "<br>"; ?>

Output:

Addition: 15 Subtraction: 5 Multiplication: 50 Division: 2 Modulus: 0 Exponentiation: 100000

In the above code, we have assigned values of 10 and 5 to variables `$a`

and `$b`

, respectively. Then, we have used arithmetic operators such as addition, subtraction, multiplication, division, modulus, and exponentiation to perform different types of operations on these variables. Finally, we have printed the result of each operation using the `echo`

statement.

### 2. PHP Assignment Operators

Assignment operators are used to assign values to variables. The assignment operators are:

- Assignment (=)
- Addition Assignment (+=)
- Subtraction Assignment (-=)
- Multiplication Assignment (*=)
- Division Assignment (/=)
- Modulus Assignment (%=)

**Here are some examples of assignment operators in PHP:**

<?php $a = 10; $b = 5; // Addition assignment $a += $b; echo "Addition assignment: " . $a . "<br>"; // Subtraction assignment $a -= $b; echo "Subtraction assignment: " . $a . "<br>"; // Multiplication assignment $a *= $b; echo "Multiplication assignment: " . $a . "<br>"; // Division assignment $a /= $b; echo "Division assignment: " . $a . "<br>"; // Modulus assignment $a %= $b; echo "Modulus assignment: " . $a . "<br>"; ?>

Output:

Addition assignment: 15 Subtraction assignment: 10 Multiplication assignment: 50 Division assignment: 10 Modulus assignment: 0

In the above code, we have assigned values of 10 and 5 to variables `$a`

and `$b`

, respectively. Then, we have used assignment operators such as addition assignment, subtraction assignment, multiplication assignment, division assignment, and modulus assignment to perform different types of operations on these variables. Finally, we have printed the result of each operation using the `echo`

statement.

### 3. PHP Comparison Operators

Comparison operators are used to compare two values. The comparison operators are:

Operators | Name | Example | Description |

== | Equal to | $x==$y | Returns true if $x is equal to $y |

=== | Identical to | $x===$y | Returns true if $x is equal and same type of $y. |

!= | Not equal to | $x != $y | Returns true if $x is not equal to $y. |

<> | Not equal to | $x <> $y | Returns true if $x is not equal to $y. |

!== | Not identical to | $x !== $y | Returns true if $x is not equal or are not the same types to $y |

> | Greater than | $x>$y | Returns true if the $x is greater than $y |

< | Less than | $x<$y | Returns true if the $x is less than $y |

>= | Greater than or equal to | $x >= $y | Returns true if the $x is greater than or equal to $y |

<= | Less than or equal to | $x <= $y | Returns true if the $x is less than or equal to $y |

**Here are some examples of comparison operators in PHP:**

<?php $a = 10; $b = 5; $c = "10"; // Equal to if ($a == $c) { echo "Equal to: true<br>"; } else { echo "Equal to: false<br>"; } // Identical to if ($a === $c) { echo "Identical to: true<br>"; } else { echo "Identical to: false<br>"; } // Not equal to if ($a != $b) { echo "Not equal to: true<br>"; } else { echo "Not equal to: false<br>"; } // Not identical to if ($a !== $c) { echo "Not identical to: true<br>"; } else { echo "Not identical to: false<br>"; } // Greater than if ($a > $b) { echo "Greater than: true<br>"; } else { echo "Greater than: false<br>"; } // Less than if ($a < $b) { echo "Less than: true<br>"; } else { echo "Less than: false<br>"; } // Greater than or equal to if ($a >= $c) { echo "Greater than or equal to: true<br>"; } else { echo "Greater than or equal to: false<br>"; } // Less than or equal to if ($a <= $c) { echo "Less than or equal to: true<br>"; } else { echo "Less than or equal to: false<br>"; } ?>

Output:

Equal to: true Identical to: false Not equal to: true Not identical to: true Greater than: true Less than: false Greater than or equal to: true Less than or equal to: true

In the above code, we have assigned values of 10 and 5 to variables `$a`

and `$b`

, respectively. We have also assigned the string value of “10” to variable `$c`

. Then, we have used comparison operators such as equal to, identical to, not equal to, not identical to, greater than, less than, greater than or equal to, and less than or equal to to compare these variables. Finally, we have printed the result of each comparison using the `echo`

statement.

### 4. PHP Increment / Decrement Operators

Increment and decrement operators are used to increase or decrease the value of a variable. The increment and decrement operators are:

Operators | Name | Description |

++$x | Pre-increment | Increments $x by one, and returns $x. |

$x++ | Post-increment | Returns $x first, then increment $x by one. |

– -$x | Pre-decrement | Decrements $x by one and returns $x. |

$x- – | Post-decrement | Returns $x first then decrements $x by one. |

**Here are some examples of increment and decrement operators in PHP:**

<?php $a = 5; // Post-increment echo "Post-increment: " . $a++ . "<br>"; echo "Value of a after post-increment: " . $a . "<br>"; // Pre-increment echo "Pre-increment: " . ++$a . "<br>"; echo "Value of a after pre-increment: " . $a . "<br>"; // Post-decrement echo "Post-decrement: " . $a-- . "<br>"; echo "Value of a after post-decrement: " . $a . "<br>"; // Pre-decrement echo "Pre-decrement: " . --$a . "<br>"; echo "Value of a after pre-decrement: " . $a . "<br>"; ?>

Output:

Post-increment: 5 Value of a after post-increment: 6 Pre-increment: 7 Value of a after pre-increment: 7 Post-decrement: 7 Value of a after post-decrement: 6 Pre-decrement: 5 Value of a after pre-decrement: 5

In the above code, we have assigned the value of 5 to variable `$a`

. Then, we have used increment and decrement operators such as post-increment, pre-increment, post-decrement, and pre-decrement to perform different types of operations on this variable. Finally, we have printed the result of each operation using the `echo`

statement.

### 5. PHP Logical Operators

Logical operators are used to combine two or more conditions. The logical operators are:

Operator | Name | Example | Result |

&& | And | $x && $y | Returns true if both $x & $y are true. |

|| | Or | $x || $y | Returns true if any of $x, $y is true. |

and | And | $x and $y | Returns true if both $x & $y are true. |

or | Or | $x or $y | Returns true if any of $x, $y is true. |

xor | Xor | $x Xor $y | Returns true if either $x or $y is true, but not both. |

! | Not | !$x<dsf | Returns true if $x is not true. |

**Here are some examples of logical operators in PHP:**

<?php $a = true; $b = false; // AND operator if ($a && $b) { echo "AND operator: true<br>"; } else { echo "AND operator: false<br>"; } // OR operator if ($a || $b) { echo "OR operator: true<br>"; } else { echo "OR operator: false<br>"; } // NOT operator if (!$a) { echo "NOT operator: true<br>"; } else { echo "NOT operator: false<br>"; } ?>

Output:

AND operator: false OR operator: true NOT operator: false

In the above code, we have assigned the boolean value of `true`

to variable `$a`

and the boolean value of `false`

to variable `$b`

. Then, we have used logical operators such as `AND`

, `OR`

, and `NOT`

to perform different types of logical operations on these variables. Finally, we have printed the result of each operation using the `echo`

statement.

### 6. PHP String Operators

String operators are used to concatenate two or more strings. The string operators are:

**.**Concatenation**.=**Combined Concatenation

Here are some examples of string operators in PHP:

<?php $a = "Hello"; $b = "World"; // Concatenation operator $c = $a . " " . $b; echo "Concatenation operator: " . $c . "<br>"; // Concatenation assignment operator $a .= " Everyone"; echo "Concatenation assignment operator: " . $a . "<br>"; ?>

Output:

Concatenation operator: Hello World Concatenation assignment operator: Hello Everyone

In the above code, we have assigned the string value of “Hello” to variable `$a`

and the string value of “World” to variable `$b`

. Then, we have used the concatenation operator `.`

to concatenate these two strings and store the result in variable `$c`

. We have printed the result using the `echo`

statement.

After that, we have used the concatenation assignment operator `.=`

to concatenate the string ” Everyone” to the existing value of variable `$a`

. We have printed the result using the `echo`

statement again.

### 7. Array Operators

Array operators are used to compare arrays. The array operators are:

- Union (+)
- Equality (==)
- Identity (===)
- Inequality (!= or <>)
- Non-identity (!==)

**Here are some examples of array operators in PHP:**

<?php // Array 1 $arr1 = array("a" => "apple", "b" => "banana", "c" => "cherry"); // Array 2 $arr2 = array("d" => "date", "e" => "elderberry", "b" => "blueberry"); // Union operator $union = $arr1 + $arr2; print_r($union); echo "<br>"; // Equality operator if ($arr1 == $arr2) { echo "Equality operator: true<br>"; } else { echo "Equality operator: false<br>"; } // Identity operator if ($arr1 === $arr2) { echo "Identity operator: true<br>"; } else { echo "Identity operator: false<br>"; } // Inequality operator if ($arr1 != $arr2) { echo "Inequality operator: true<br>"; } else { echo "Inequality operator: false<br>"; } // Non-identity operator if ($arr1 !== $arr2) { echo "Non-identity operator: true<br>"; } else { echo "Non-identity operator: false<br>"; } ?>

Output:

Array ( [a] => apple [b] => banana [c] => cherry [d] => date [e] => elderberry ) Equality operator: false Identity operator: false Inequality operator: true Non-identity operator: true

In the above code, we have created two arrays `$arr1`

and `$arr2`

. We have used array operators such as union operator `+`

, equality operator `==`

, identity operator `===`

, inequality operator `!=`

, and non-identity operator `!==`

to perform different types of operations on these arrays.

The union operator `+`

combines the key-value pairs of both arrays and creates a new array. The equality operator `==`

checks if the two arrays have the same key-value pairs, regardless of their order. The identity operator `===`

checks if the two arrays have the same key-value pairs in the same order. The inequality operator `!=`

checks if the two arrays do not have the same key-value pairs, regardless of their order. The non-identity operator `!==`

checks if the two arrays do not have the same key-value pairs in the same order.

Finally, we have printed the result of each operation using the `print_r`

statement and the `echo`

statement.

### 8. Conditional assignment operators

Conditional assignment operators in PHP are shorthand operators that combine a conditional expression with an assignment. These operators are useful for assigning a value to a variable only if a certain condition is met.

**There are two types of conditional assignment operators in PHP:**

- Ternary operator (
`?:`

) - Null coalescing operator (
`??`

)

#### 1. Ternary operator (`?:`

)

This operator is a shorthand way of writing an if-else statement. The syntax of the ternary operator is as follows:

$variable = (condition) ? value_if_true : value_if_false;

If the condition is true, the value of `$variable`

will be set to `value_if_true`

, otherwise it will be set to `value_if_false`

.

**Here’s an example of the ternary operator in action:**

<?php // Ternary operator $age = 20; $isAdult = ($age >= 18) ? "Yes" : "No"; echo "Is the person an adult? " . $isAdult; ?>

Output:

Is the person an adult? Yes

In the above code, we have used the ternary operator to set the value of `$isAdult`

to “Yes” if the value of `$age`

is greater than or equal to 18, and “No” otherwise. We have printed the result using the `echo`

statement.

#### 2. Null coalescing operator (`??`

)

This operator checks if a variable is null, and if it is, assigns a default value. The syntax of the null coalescing operator is as follows:

$variable = $value ?? $default_value;

If `$value`

is not null, the value of `$variable`

will be set to `$value`

, otherwise it will be set to `$default_value`

.

**Here’s an example of the null coalescing operator in action:**

<?php // Null coalescing operator $username = $_POST["username"] ?? "Guest"; echo "Welcome, " . $username; ?>

In the above code, we have used the null coalescing operator to set the value of `$username`

to the value of `$_POST["username"]`

if it is not null, and “Guest” otherwise. We have printed the result using the `echo`

statement.