Example 1: how to filter object in javascript
// use filter() function. Let say we have array of object.
let arr = [
{name: "John", age: 30},
{name: "Grin", age: 10},
{name: "Marie", age: 50},
];
//Now I want an array in which person having age more than 40 is not
//there, i.e, I want to filter it out using age property. So
let newArr = arr.filter((person)=>(return person.age <= 40));
//filter function expects a function if it return true then it added
//into new array, otherwise it is ignored. So new Array would be
/* [
{name: "John", age: 30},
{name: "Grin", age: 10},
]
*/
Example 2: how to filter an array of objects in javascript
let arr=[{id:1,title:'A', status:true}, {id:3,title:'B',status:true}, {id:2, title:'xys', status:true}];
//find where title=B
let x = arr.filter((a)=>{if(a.title=='B'){return a}});
console.log(x)//[{id:3,title:'B',status:true}]
Example 3: js filter array of objects by value
var heroes = [
{name: “Batman”, franchise: “DC”},
{name: “Ironman”, franchise: “Marvel”},
{name: “Thor”, franchise: “Marvel”},
{name: “Superman”, franchise: “DC”}
];
var marvelHeroes = heroes.filter(function(hero) {
return hero.franchise == “Marvel”;
});
// [ {name: “Ironman”, franchise: “Marvel”}, {name: “Thor”, franchise: “Marvel”} ]
Example 4: who to accses to an object vallue inside an array with .filter method js
const array = [
{
username: "john",
team: "red",
score: 5,
items: ["ball", "book", "pen"]
},
{
username: "becky",
team: "blue",
score: 10,
items: ["tape", "backpack", "pen"]
},
{
username: "susy",
team: "red",
score: 55,
items: ["ball", "eraser", "pen"]
},
{
username: "tyson",
team: "green",
score: 1,
items: ["book", "pen"]
},
];
//FILTER MEMBERS IN TEAM "RED"
const filterArray=array.filter(word=>word.team==="red")
Example 5: javascript filter array of objects
let people = [
{ name: "Steve", age: 27, country: "America" },
{ name: "Jacob", age: 24, country: "America" }
];
let filteredPeople = people.filter(function (currentElement) {
// the current value is an object, so you can check on its properties
return currentElement.country === "America" && currentElement.age < 25;
});
console.log(filteredPeople);
// [{ name: "Jacob", age: 24, country: "America" }]
Example 6: javascript filter array of objects by array
var arr = [1,2,3,4],
brr = [2,4],
res = arr.filter(f => !brr.includes(f));
console.log(res);