JAVASCRIPT

lodash remove undefined values from array

var colors = ["red",undefined,"","blue",null,"crap"];
// remove undefined, null, "" and any other crap
var cleanColors=_.without(colors,undefined,null,"","crap");
//cleanColors is now ["red","blue"];

lodash remove undefined values from object

var person = {"name":"bill","age":21,"sex":undefined,"height":"crap"};
//remove undefined properties or other crap
var cleanPerson = _.pickBy(person, function(value, key) {
  return !(value === undefined || value === "crap");
});
//cleanPerson is now { "name": "bill","age": 21}

lodash remove element from array

var colors = ["red","blue","green","green"];
var greens = _.remove(colors, function(c) {
    return (c === "green"); //remove if color is green
});
//colors is now ["red","blue"]
//greens is now ["green","green"]

lodash remove not in array

var a = [
  {id: 1, name: 'A'},
  {id: 2, name: 'B'},
  {id: 3,  name: 'C'},
  {id: 4, name: 'D'}
];
var removeItem = [1,2];
removeItem.forEach(function(id){
   var itemIndex = a.findIndex(i => i.id == id);
   a.splice(itemIndex,1);
});
console.log(a);