What's the Difference Between the `||` (Logical OR) and `|` (Bitwise OR) Operators in Programming?

The Difference between | and || Operators

Question:

In programming languages such as C# and PHP, what is the distinction between the || (or) and | operators? Are they interchangeable, or are there specific application cases for each?

Answer:

Similar to the & and && operators, the || (also known as logical OR) and | (bitwise OR) operators handle logical and bitwise operations differently.

Logical OR (||):

• A short-circuit operator: If the first condition evaluates to true, it will skip checking the remaining conditions.
• Used in OR expressions where you intend to check only the necessary conditions to determine the overall result.

• Example:

  if(condition1 || condition2 || condition3)

  If condition1 is true, condition2 and condition3 will not be evaluated.

Bitwise OR (|):

• Performs bitwise operations: Compares bits at corresponding positions and sets the result bit to 1 if at least one of the input bits is 1.
• Used in situations where you want to perform bitwise manipulations on binary values.

• Example:

  x | y

  Sets each bit in the result to 1 if the corresponding bit in either x or y is 1.

Caveats:

One notable caveat when using logical OR is handling null references:

if(class != null || class.someVar < 20)

If class is null, the && operator will short-circuit and avoid checking class.someVar, while | may trigger an exception.

Rare Usage of Single Operators:

The & and | operators are rarely used independently, as they typically require each function to be executed (unlike && and ||). However, they may be useful in scenarios where each condition is a function that must be executed unconditionally.

The above is the detailed content of What's the Difference Between the `||` (Logical OR) and `|` (Bitwise OR) Operators in Programming?. For more information, please follow other related articles on the PHP Chinese website!