Assignment Operator

Concatenation (.=)

$address = "Beautiful Street";
$city = "New City";
echo $address . " " . $city;
$province = "Great Province";
$address .= " " . $city . " " . $province;
echo $address;

Addition (+=)

$amount = 100;
$amount = $amount + 1;
$amount += 1;
echo $amount;

Subtraction (-=)

$amount = 100;
$amount = $amount - 1;
$amount -= 1;
echo $amount;

Multiplication (*=)

$amount = 100;
$amount = $amount * 2;
$amount *= 2;
echo $amount;

Division (/=)

$amount = 100;
$amount = $amount / 2;
$amount /= 2;
echo $amount;

Modulus (%=)

$amount = 100;
$amount = $amount % 2;
$amount %= 2;
echo $amount;

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Increment Operator

Pre Increment (++)

$amount = 100;
echo ++$amount;
echo $amount;

Post Increment

$amount = 100;
echo $amount++;
echo $amount;

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Decrement Operator

Pre Decrement (--)

$amount = 100;
echo --$amount;
echo $amount;

Post Decrement

$amount = 100;
echo $amount--;
echo $amount;

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Expression Operators

Comparison operator (==)

$activeFlag = 1;
$active = 1;
echo  ($activeFlag == $active) ? "Active" : "Inactive"; // always use == for comparison instead of = sign. 

Identical operator (===)

$val_1 = 10;
$val_2 = "10";
echo ($val_1 == $val_2) ? "true" : "false";
echo ($val_1 === $val_2) ? "true" : "false";

Not Equal To (!=)

$activeFlag = 1;
$active = 1;
echo  ($activeFlag != $active) ? "Active" : "Inactive";

Exponential operator (**)

echo (2 ** 3);

Logical Operators

And operator (&&)

$min_value = 1;
$max_value = 100;
$input = 50;
echo  ($input >= $min_value && $input <= $max_value) ? "Valid input" : "Invalid input";

$result = true && false;
echo $result ? "true" : "false";

And operator (and) (operator = has precedence over operator and)

$result = true and false;
echo $result ? "true" : "false";

Or Operator (||)

$min_value = 100;
$max_value = 200;
$input = 150;
echo  ($input >= $min_value || $input <= $max_value) ? "Valid input" : "Invalid input";

Or operator (or) (operator = has precedence over operator or)

$result = false or true;
echo $result ? "true" : "false";

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Bitwise Operators

And operator (&)

$stored_bit = 0; // 0000
$input_bit = 1;  // 0001
echo  ($stored_bit & $input_bit); // (0000) & (0001) => 0

$stored_bit = 2; // 0010
$input_bit = 3;  // 0011
echo  ($stored_bit & $input_bit); // (0010) & (0011) => 2

Or operator (|)

$stored_bit = 0; // 0000
$input_bit = 1;  // 0001
echo  ($stored_bit | $input_bit); // (0000) | (0001) => 1

$stored_bit = 2; // 0010
$input_bit = 3;  // 0011
echo  ($stored_bit & $input_bit) ; // (0010) | (0011) => 3 

xor operator (^)

$stored_bit = 2; // 0010
$input_bit = 3;  // 0011
echo  ($stored_bit ^ $input_bit); // (0010) ^ (0011) => 1  - because 0 ^ 1 => 1, 1 ^ 1 => 0

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Execution operator (``) backtick

$name = "PHP";
$command = "echo Hello $name";
echo  `$command`; // use backtick for executing command.

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Error Control Operator

$amount = 100;
@$avg = $amount / 0; // will raise an error but due to @ symbol it will not display the error.
echo  (isset($php_errormsg)) ? "Error " . $php_errormsg : ""