JavaScript Boolean Reference Next ... W3Schools is optimized for learning, testing, and training. The value passed as the first parameter is converted to a boolean value, if necessary. A JavaScript Boolean represents one of two values: true or false. Examples might be simplified to improve reading and basic understanding. 在 JavaScript 中，布尔值是一种基本的数据类型。 ... W3School 简体中文版提供的内容仅用于培训和测试，不保证内容的正确性。通过使用本站内容随之而来的风险与本站无关。版权所有，保留一切权利。 Boolean 对象描述. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. Examples might be simplified to improve reading and basic understanding. Boolean Values. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. W3Schools is optimized for learning, testing, and training.

... W3Schools is optimized for learning, testing, and training. Examples might be simplified to improve reading and basic understanding. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. W3Schools is optimized for learning, testing, and training. If the value is omitted or is 0, -0, null, false, NaN, undefined, or the empty string (\"\"), the object has an initial value of false. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. While using this site, you agree to have read and accepted our It slows down execution speed.The reference contains descriptions and examples of all Boolean properties and methods.If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail: Very often, in programming, you will need a data type that can only have one of two values, like: ... W3Schools is optimized for learning, testing, and training. Will it produce an error or will it produce a result?JavaScript will treat the example above as:JavaScript evaluates expressions from left to right. Examples might be simplified to improve reading and basic understanding. JavaScript Reference HTML DOM Reference jQuery Reference AngularJS Reference W3.JS Reference ... Java Booleans. W3Schools is optimized for learning, testing, and training. Previous JavaScript Boolean Reference Next ... W3Schools is optimized for learning, testing, and training. Very often, in programming, you will need a data type that can only have one of two values, like. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. (see below).The Boolean value of an expression is the basis for all Java comparisons and conditions.You will learn more about conditions in the next chapter.If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail: While using this site, you agree to have read and accepted our of two values, likeThe chapter JS Comparisons gives a full overview of comparison operators.The chapter JS Conditions gives a full overview of conditional statements.The Boolean value of an expression is the basis for all JavaScript comparisons and conditions.Normally JavaScript booleans are primitive values created from literals:But booleans can also be defined as objects with the keyword Do not create Boolean objects. Examples might be simplified to improve reading and basic understanding. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. Very often, in programming, you will need a data type that can only have one of two values, like:However, it is more common to return boolean values from boolean expressions, for conditional testing W3Schools is optimized for learning, testing, and training. In programming, data types is an important concept.To be able to operate on variables, it is important to know something about the type.Without data types, a computer cannot safely solve this:Does it make any sense to add \"Volvo\" to sixteen? Examples are often easier to understand than text explanations.This tutorial supplements all explanations with clarifying \"Try it Yourself\" examples.JavaScript Examples Examples might be simplified to improve reading and basic understanding. A JavaScript Boolean represents one of two values: Very often, in programming, you will need a data type that can only have one Examples might be simplified to improve reading and basic understanding. Examples are better than 1000 words.