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:trueandfalse.

Creating Boolean values

Boolean values can be created in the following ways:

• Boolean literals:trueorfalse
• Boolean()Constructor: It converts any value to the corresponding Boolean value (for example,Boolean(0)isfalse,Boolean("hello")istrue)

Comparison and condition

Boolean values are mainly used for comparisons and conditions:

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

Logical operators

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

• Logical AND (&&):Returnstrueonly if both operands aretrue(e.g.,true && trueistrue)
• Logical OR (||):Returnstrueonly when either operand istrue(for example,false || trueistrue)
• Logical NOT (!):Invert the Boolean value,truebecomesfalse,falsebecomestrue(for example,!truebecomesfalse)

Note

• In JavaScript, empty strings (""),nullandundefinedare considered isfalse.
• Any non-zero number is consideredtrue, even if it is negative.
• When using theBoolean()constructor, the results may be different than expected because the constructor changes certain values (such as0and" ") is converted totrue.

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

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