How to iterate over a JavaScript object?

Question

I have an object in JavaScript:

{
    abc: \'...\',
    bca: \'...\',
    zzz: \'...\',
    xxx: \'...\',
    ccc: \'...\',
    // ...
}

I

Answer 1

If you have a simple object you can iterate through it using the following code:

let myObj = {
  abc: '...',
  bca: '...',
  zzz: '...',
  xxx: '...',
  ccc: '...',
  // ...
};

let objKeys = Object.keys(myObj);

//Now we can use objKeys to iterate over myObj

for (item of objKeys) {
  //this will print out the keys
  console.log('key:', item);
  
  //this will print out the values 
  console.log('value:', myObj[item]);
}

If you have a nested object you can iterate through it using the following code:

let b = {
  one: {
    a: 1,
    b: 2,
    c: 3
  },
  two: {
    a: 4,
    b: 5,
    c: 6
  },
  three: {
    a: 7,
    b: 8,
    c: 9
  }
};

let myKeys = Object.keys(b);

for (item of myKeys) {
  //print the key
  console.log('Key', item)
  
  //print the value (which will be another object)
  console.log('Value', b[item])
  
  //print the nested value
  console.log('Nested value', b[item]['a'])
}

If you have array of objects you can iterate through it using the following code:

let c = [
{
  a: 1,
  b: 2
},
{
  a: 3,
  b: 4
}
];

for(item of c){
//print the whole object individually 
console.log('object', item);

//print the value inside the object
console.log('value', item['a']);
}