loop through array inside object javascript code example

Example 1: how to iterate object inside object in javascript

let obj = {
  key1: "value1",
  key2: "value2",
  key3: "value3"
}
for (let key in obj) {
  let value = obj[key];
  console.log(key, value);
}
// key1 value1
// key2 value2
// key3 value3

Example 2: javascript loop through array of objects

var arr = [{id: 1},{id: 2},{id: 3}];

for (var elm of arr) {
  console.log(elm);
}

Example 3: how to loop through an array of objects+

var arr = [[1,2], [3,4], [5,6]];
 for (var i=0; i < arr.length; i++) {
  for (var j=0; j < arr[i].length; j++) {
    console.log(arr[i][j]);
  }
}