PHP provides a set of bitwise operators that allow you to work directly with the binary representation of numbers. These operators perform bit-level operations, which can be useful for tasks such as flag handling and low-level programming.
1. Common Bitwise Operators
&: Bitwise AND|: Bitwise OR^: Bitwise XOR~: Bitwise NOT (Complement)<<: Left Shift>>: Right Shift
2. How Bitwise Operators Work
Bitwise operators work on the binary representation of integers. For example, consider the numbers 5 and 3:
- 5 in binary is 0101
- 3 in binary is 0011
📝 Example 1: Bitwise AND (&)
Performs AND operation between two numbers.
<?php
$a = 6; // 110 in binary
$b = 3; // 011 in binary
echo $a & $b; // Output: 2 (010 in binary)
?>
📝 Example 2: Bitwise OR (|)
Returns 1 if at least one bit is 1.
<?php
$a = 6; // 110 in binary
$b = 3; // 011 in binary
echo $a | $b; // Output: 7 (111 in binary)
?>
📝 Example 3: Bitwise XOR (^)
Returns 1 if only one of the bits is 1.
<?php
$a = 6; // 110 in binary
$b = 3; // 011 in binary
echo $a ^ $b; // Output: 5 (101 in binary)
?>
📝 Example 4: Bitwise NOT (~)
Flips all bits of a number (may give negative results due to 2’s complement representation).
<?php
$a = 6; // 110 in binary
echo ~ $a; // Output: -7 (due to 2's complement)
?>
📝 Example 5: Left Shift (<<)
Moves bits to the left (multiplies by powers of 2).
<?php
$a = 3; // 011 in binary
echo $a << 2; // Output: 12 (1100 in binary)
?>
📝 Example 6: Right Shift (>>)
Moves bits to the right (divides by powers of 2).
<?php
$a = 8; // 1000 in binary
echo $a >> 2; // Output: 2 (10 in binary)
?>
🎯 Recap – Quick Takeaways
&(AND) → Both bits must be 1|(OR) → At least one bit must be 1^(XOR) → Only one bit can be 1~(NOT) → Flips all bits<<(Left Shift) → Moves bits left, fills with 0s>>(Right Shift) → Moves bits right, discards bits
📝 Practice Time!
Change values in the examples and see what happens. The best way to learn is to experiment!