add after ary assign assignIn assignInWith assignWith at before bind bindAll bindKey camelCase capitalize castArray ceil chain chunk clamp clone cloneDeep cloneDeepWith cloneWith compact concat conformsTo countBy create curry curryRight debounce deburr defaults defaultsDeep defer delay difference divide drop dropRight each eachRight endsWith entries entriesIn eq escape every extend extendWith fill filter find findIndex findKey findLast findLastIndex findLastKey first flatMap flatMapDeep flatMapDepth flatten flattenDeep flattenDepth flip floor forEach forEachRight forIn forInRight forOwn forOwnRight fromPairs functions functionsIn get groupBy gt gte has hasIn head inRange includes indexOf initial intersection invert invertBy invoke invokeMap isArguments isArray isArrayBuffer isArrayLike isArrayLikeObject isBoolean isBuffer isDate isElement isEmpty isEqual isEqualWith isError isFinite isFunction isInteger isLength isMap isMatch isMatchWith isNaN isNative isNil isNull isNumber isObject isObjectLike isPlainObject isRegExp isSafeInteger isSet isString isSymbol isTypedArray isUndefined isWeakMap isWeakSet join kebabCase keyBy keys keysIn last lastIndexOf lowerCase lowerFirst lt lte map mapKeys mapValues max maxBy mean meanBy memoize merge mergeWith min minBy multiply negate nth omit omitBy once orderBy overArgs pad padEnd padStart parseInt partial partialRight partition pick pickBy pull pullAll pullAllBy pullAllWith pullAt random rearg reduce reduceRight reject remove repeat replace rest result reverse round sample sampleSize set setWith shuffle size slice snakeCase some sortBy sortedIndex sortedIndexOf sortedLastIndex sortedLastIndexOf sortedUniq split spread startCase startsWith subtract sum sumBy tail take takeRight tap template throttle thru toArray toFinite toInteger toLength toLower toNumber toPairs toPairsIn toPlainObject toSafeInteger toString toUpper transform trim trimEnd trimStart truncate unary unescape union uniq uniqBy uniqWith unset unzip unzipWith update updateWith upperCase upperFirst values valuesIn without words wrap wrapperAt wrapperChain wrapperCommit wrapperFlatMap wrapperLodash wrapperNext wrapperPlant wrapperReverse wrapperToIterator wrapperValue xor zip zipObject zipObjectDeep zipWith

Lodash _.size

Overview

The _.size method in Lodash is a utility function that returns the number of elements in a collection. This method can be used with arrays, objects, and strings in JavaScript.

Syntax:

_.size(collection)

Parameters:

  • collection (Array|Object|string): The collection to inspect.

Return Value:

  • (number): Returns the size of the collection.

Examples:

  1. Using _.size with an array:
const arr = [1, 2, 3, 4, 5];
const size = _.size(arr);
console.log(size); // Output: 5
  1. Using _.size with an object:
const obj = {
  name: 'John',
  age: 30,
  city: 'New York'
};
const size = _.size(obj);
console.log(size); // Output: 3
  1. Using _.size with a string:
const str = 'hello world';
const size = _.size(str);
console.log(size); // Output: 11

Notes:

  • For arrays and strings, _.size returns the number of elements in the collection.
  • For objects, _.size returns the number of enumerable properties in the object.
  • If the collection is null or undefined, _.size returns 0.
  • If the collection is not an array, object, or string, _.size returns undefined.
  • This method is part of the Lodash library, which is a popular utility library for JavaScript. To use _.size, you must first include the Lodash library in your project.

In conclusion, the _.size method in Lodash is a simple and useful utility function that returns the number of elements in a collection. It can be used with arrays, objects, and strings in JavaScript, and it returns 0 for null or undefined collections. By using this method, developers can easily get the size of a collection without having to write complex code.