Logical operators

TypeScript supports the following logical operators. To understand the examples, you must assume that variable A holds 10 and variable B holds 20:

Operator

Description

Example

&&

Known as the logical AND operator. If both the operands are nonzero, then the condition becomes true.

(A && B) is true.

||

Known as the logical OR operator. If any of the two operands are nonzero, then the condition becomes true.

(A || B) is true.

!

Known as the logical NOT operator. It is used to reverse the logical state of its operand. If a condition is true, then the logical NOT operator will make it false.

!(A && B) is false.

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