Usage of boolean in js

The Boolean type in JavaScript represents true and false values, and the value is true or false. Can be created using literals or the Boolean() constructor for use in comparisons and conditional statements. Logical operators (AND, OR, NOT) operate on Boolean values. Note that empty strings, null, and undefined are considered false, while non-zero numbers are considered true. Proper use of the Boolean type is critical to writing robust JavaScript code.

Usage of Boolean in JavaScript

The Boolean type in JavaScript is used to represent true and false values. It has only two possible values: true and false.

Creating Boolean values

Boolean values ​​can be created in the following ways:

• Boolean literals: true or false
• Boolean() Constructor: It converts any value to the corresponding Boolean value (for example, Boolean(0) is false, Boolean("hello") is true)

Comparison and condition

Boolean values ​​are mainly used for comparisons and conditions:

• Comparison: Use == or === operator comparison Boolean value (for example, true == false returns false)
• Condition: in if, Use Boolean values ​​to control code flow in conditional statements such as while and for (for example, if (condition) { ... })

Logical operators

JavaScript also provides the following logical operators for operating Boolean values:

• Logical AND (&&): Returns true only if both operands are true (e.g., true && true is true)
• Logical OR (||): Returns true only when either operand is true (for example, false || true is true)
• Logical NOT (!): Invert the Boolean value, true becomes false , false becomes true (for example, !true becomes false)

Note

• In JavaScript, empty strings (""), null and undefined are considered is false.
• Any non-zero number is considered true, even if it is negative.
• When using the Boolean() constructor, the results may be different than expected because the constructor changes certain values ​​(such as 0 and " ") is converted to true.

Understanding the usage of the Boolean type is critical to writing robust and readable JavaScript code.

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