How to remove Objects from an array of objects using JavaScript?

Question

I have an array of objects where some objects are undefined and I want to know how to remove them i got it how many of them but don't know how to remove them from an array of objects. i know this method to use but i want some more standard way to do it

 const data = [
 {
 roleDoc:{
 name:"A"
 }
 },
 { roleDoc: undefined }
 ,{
 roleDoc:{
 name:"c"
 }
 },{
 roleDoc:{
 name:"c"
 }
 },
 { roleDoc: undefined },
 ,{
 roleDoc:{
 name:"c"
 }
 }
 ]
 const xy = []
data.forEach(item => {
 if(item.roleDoc !== undefined){
 xy.push(item) 
 }
 else{
 console.log('hello')
 }
})
console.log(xy)

expected output is

const data = [
 {
 roleDoc: {
 name: "A"
 }
 },
 ,
 {
 roleDoc: {
 name: "c"
 }
 },
 {
 roleDoc: {
 name: "c"
 }
 },
 ,
 {
 roleDoc: {
 name: "c"
 }
 }
];

Answer 1

You could do with Array#filter and !! only matched valid

const data = [ { roleDoc:{ name:"A" } }, { roleDoc: undefined } ,{ roleDoc:{ name:"c" } },{ roleDoc:{ name:"c" } }, { roleDoc: undefined },{ roleDoc:{ name:"c" } }];
let res = data.filter(a=> !!a.roleDoc);
console.log(res)

Answer 2

You can use .filter() to remove undefined ones.

Try the following:

 const data = [{ roleDoc:{ name:"A" } }, { roleDoc: undefined } ,{ roleDoc:{ name:"c"}},{roleDoc:{name:"c"} }, { roleDoc: undefined },{ roleDoc:{name:"c"}}];
const result = data.filter(e => e.roleDoc);
console.log(result);

I hope this helps!

Answer 3

You could use a function programming approach using the Array.filter function:

const data = [
 {
 roleDoc: {
 name: "A"
 }
 },
 { 
 roleDoc: undefined 
 },
 {
 roleDoc: {
 name: "c"
 }
 },
 {
 roleDoc: {
 name: "c"
 }
 },
 { 
 roleDoc: undefined
 },
 {
 roleDoc: {
 name: "c"
 }
 }
];
const arrayWithoutUndefineds = data.filter(el => typeof el.roleDoc !== 'undefined');
console.log(arrayWithoutUndefineds);

Note that the expression used could be simplied. However, so it it clear what it happening I will leave it there.