Collect.js whereInstanceOf() function

0 0 1 minute read

The whereInstanceOf() function is used to filter input with a given class type. In JavaScript, the array is first converted to a collection and then the function is applied to the collection.

Syntax:

data.whereInstanceOf('key')

Parameters: This function accepts a single parameter as mentioned above and described below:

Key: This parameter holds the key name that defines the value of that key.

Return value: Return the collection with a key value that was mentioned.
Below examples illustrate the whereInstanceOf() function in collect.js
Example 1: Here in this example, we take a collection and then using the whereInstanceOf() method we have returned filtered collection using the key.

Javascript

// It is used to import collect.js library 
const collect = require('collect.js'); 
  
const Input = collect([ 
  new Books('Pride and prejudice'), 
  new Books('The Great Gatsby '), 
  new Movies('It'), 
]); 
  
const output = Input.whereInstanceOf(Books); 
console.log(output.all()); 

Output:

[
   new Books('Pride and prejudice'),
   new Books('The Great Gatsby'),
]

Example 2: Same thing we have done here as the above example.

Javascript

// It is used to import collect.js library 
const collect = require('collect.js'); 
  
const Input = collect([ 
  new Year('1980'), 
  new Year('2020'), 
  new Name('Mohan'), 
]); 
  
const output = Input.whereInstanceOf(Name); 
  
console.log(output.all()); 

Output:

[
  new Name('Mohan'),
]

References: https://collect.js.org/api/whereinstanceof.html

Whether you’re preparing for your first job interview or aiming to upskill in this ever-evolving tech landscape, zambiatek Courses are your key to success. We provide top-quality content at affordable prices, all geared towards accelerating your growth in a time-bound manner. Join the millions we’ve already empowered, and we’re here to do the same for you. Don’t miss out – check it out now!