Tips code Javascript

let variable2;
if (variable1 !== null || variable1 !== undefined || variable1 !== '') {
     variable2 = variable1;
} else {
    variable2 = "";
}

const variable2 = variable1  || "";

var someJsonArray = [
  {id: 0, name: "name", property: "value", therproperties: "othervalues"},
  {id: 1, name: "name1", property: "value1", otherproperties: "othervalues1"},
  {id: 2, name: "name2", property: "value2", otherproperties: "othervalues2"}
];
var finalArray = someJsonArray.map(function (obj) {
  return obj.id;
});
console.log(finalArray); ==> Kết Quả:[0, 1, 2]