Lodash _.isArray() Method

Syntax, Parameter and Return Value

Syntax: 

_.isArray(value)

Parameters:

value: The value to check.

Return Value: 

(boolean) - Returns true if value is an array, else false.

Examples 

Basic Array Check:

• JavaScript

JavaScript

var _ = require('lodash');

console.log(_.isArray([1, 2, 3])); 

console.log(_.isArray({ a: 1, b: 2 })); 

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Output: 

true
false

Demonstrates the basic usage of _.isArray() for identifying arrays.

Conditionally Processing Data:

function processData(data) {
  if (_.isArray(data)) {
    // Handle array-specific logic
  } else {
    // Handle non-array data
  }
}

Shows conditional data processing based on whether the input is an array.

Using in Combination with Other Lodash Methods:

• JavaScript

JavaScript

var data = [1, 2, 3];

if (_.isArray(data)) {

  var doubled = _.map(data, x => x * 2);

  console.log(doubled);

}

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Output: 

[2, 4, 6]

An example of using _.isArray() before applying array-specific operations like mapping.

Filtering Arrays in a Collection:

• JavaScript

JavaScript

var mixedCollection = [1, 'string', [2, 3], { a: 4 }];

var arrays = _.filter(mixedCollection, _.isArray);

console.log(arrays);

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Output:

[[2, 3]]

Demonstrates filtering out arrays from a mixed collection of items.

Frequently Asked Questions

How is _.isArray() different from JavaScript's Array.isArray()?

_.isArray() and JavaScript's native Array.isArray() function similarly. The primary difference is that _.isArray() is part of the Lodash library, which provides consistency and compatibility across various environments and versions of JavaScript.

Can _.isArray() detect array-like objects?

No, _.isArray() specifically checks for true arrays. Array-like objects (e.g., arguments object, NodeList) return false.

Is _.isArray() necessary with modern JavaScript?

While modern JavaScript provides Array.isArray(), using _.isArray() can be beneficial for consistency when using Lodash for other utilities, or in environments where Array.isArray() is not available or reliable.

Conclusion

Lodash's _.isArray() method provides a straightforward and reliable way to check for arrays in JavaScript. It's a useful utility for ensuring correct handling of data structures, particularly when dealing with complex collections or mixed data types.

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