Example 1: array.filter in js
var numbers = [1, 3, 6, 8, 11];
var lucky = numbers.filter(function(number) {
return number > 7;
});
Example 2: array filter
const words = ['spray', 'limit', 'elite', 'exuberant', 'destruction', 'present'];
const result = words.filter(word => word.length > 6);
console.log(result);
// expected output: Array ["exuberant", "destruction", "present"]
Example 3: javascript array filter
var newArray = array.filter(function(item) {
return condition;
});
Example 4: js filter items by index
let newArray = arr.filter(callback(element[, index, [array]])[, thisArg])
Example 5: js filter object of objects
// Our data
const fruits = {
apple: {
qty: 300,
color: "green",
name: "apple",
price: 2
},
banana: {
qty: 130,
color: "yellow",
name: "banana",
price: 3
},
orange: {
qty: 120,
color: "orange",
name: "orange",
price: 1.5
},
melon: {
qty: 70,
color: "yellow",
name: "melon",
price: 5
}
};
// Now let"s create a map function
const map = (obj, fun) =>
Object.entries(obj).reduce(
(prev, [key, value]) => ({
...prev,
[key]: fun(key, value)
}),
{}
);
// Finally let's map by color for example
const myFruits = map(fruits, (_, fruit) => fruit.color);
/*
{ apple: 'green',
banana: 'yellow',
orange: 'orange',
melon: 'yellow' }
/*