Array.prototype.find to search for an object in an array

Question

I use Array.prototype.find to search for an Object in an array. I would like to use an identifier to find this object. I read about the find method (ES6), but I don't know why my code is wrong.

This is my code:

AddresBook.prototype.getPerson = function (id) {

    return this.lisPerson.find(buscarPersona, id);

};

function buscarPersona(element, index, array) {
    if (element.id === this.id) {
        return element;
    } else
        return false;
}

Answer 1

You pass iddirectly as a parameter to , but internally you are expecting for an object with a property . Therefore either thisArg.find()buscarPersonathis.id

• pass object:

  lisPerson.find(buscarPersona, {id});
  function buscarPersona(element, index, array) {
      return element.id === this.id;
  }
  

• use thisdirectly:

  lisPerson.find(buscarPersona, id);
  function buscarPersona(element, index, array) {
      // works in strict mode only, make sure to use it
      return element.id === this;
  }
  

• just skip closing

  lisPerson.find(element => element.id === id);
  

Answer 2

AddressBook's last_id .

,

AddressBook.prototype.getPerson = function(id){
    this.last_id = id;
    return this.lisPerson.find(buscarPersona,this);
}
function buscarPersona(element){
    if(element.id === this.last_id){
        return element;
    }else{
        return false;   
    }
}