30秒学会 JavaScript 片段 – isEmpty

Returns true if the a value is an empty object, collection, has no enumerable properties or is any type that is not considered a collection.

Check if the provided value is null or if its length is equal to 0.

代码片段

const isEmpty = val => val == null || !(Object.keys(val) || val).length;

使用样例

isEmpty([]); // true
isEmpty({}); // true
isEmpty(''); // true
isEmpty([1, 2]); // false
isEmpty({ a: 1, b: 2 }); // false
isEmpty('text'); // false
isEmpty(123); // true - type is not considered a collection
isEmpty(true); // true - type is not considered a collection