What does || mean in php?

The || operator in PHP represents logical OR and is used to connect Boolean expressions. If the left operand is TRUE, the entire expression is TRUE, regardless of the right operand; if the left operand is FALSE, the expression continues to evaluate the right operand, and if the right operand is TRUE, the expression is TRUE. Unlike the && operator, the latter's rule is that both operands are TRUE. The advantage of the || operator is that it can be used when at least one expression is TRUE, which can simplify complex Boolean expressions. It is often used to check whether at least one of multiple conditions is TRUE, or to see whether an item is in a list.

The meaning of || in PHP

|| in PHP is a logical OR operator, used for connection Boolean expression. It follows the following rules:

• If the left operand is TRUE, the entire expression is TRUE, regardless of the right operand.
• If the left operand is FALSE, the expression continues to evaluate the right operand.
• If the right operand is TRUE, the entire expression is TRUE.
• If the right operand is FALSE, the entire expression is FALSE.

Example:

<code class="php">$a = true;
$b = false;

// 如果 $a 为 true，则 $a || $b 为 true，无论 $b 的值是什么。
if ($a || $b) {
    // 执行代码
}

// 如果 $a 为 false，则 $a || $b 继续评估 $b。
if ($a || $b) {
    // 不执行代码，因为 $b 为 false
}</code>

Differences from && operator:

&& operator (logical AND) is also used to join Boolean expressions, but it follows different rules:

• The entire expression is TRUE only if both operands are TRUE.
• As long as one operand is FALSE, the entire expression is FALSE.

|| Advantages of the operator: The

• || operator can be used when at least one Boolean expression is required to be TRUE.
• It can simplify complex Boolean expressions.

Usage scenarios:

|| Operator is usually used in the following scenarios:

• Check at least one of multiple conditions one.
• Check whether certain items are in the list.
• Perform an operation that is performed only when a certain condition is met.

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