The where() function is used to filter the collection by a given key or value contained within the given array. In JavaScript, the array is first converted to a collection and then the function is applied to the collection.
Syntax:
data.where('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 where() function in collect.js:
Example 1: Here in this example, we take a collection and then using the where() method we have returned filtered collection using the key.
Javascript
// It is used to import collect.js libraryÂ
const collection = collect([  { Book: 'Let US C', price: 2000 },  { Book: 'Begin Python', price: 1000 },  { Book: 'Learn the DEV', price: 1500 },]);Â
const filtered = collection.where('price', [1000, 1500]);filtered.all(); |
Output:
[
{ Book: 'Begin Python', price: 1000 },
{ Book: 'Learn the DEV', price: 1500 }
]
Example 2:
Javascript
// It is used to import collect.js library const collect = require('collect.js'); Â
const Input = collect([ Â Â new Year('1980'), Â Â new Year('2020'), Â Â new Year('2025'), ]); Â
const output = Input.where('Year',[2000, 2025]); Â
console.log(output.all()); |
Output:
[
new Year('2025')
]
Reference: https://collect.js.org/api/where.html
