Whats wrong with this simple for...in loop

Since the goal is to get the object's properties and values, where the object is inside an array, we will need to use two (2) loops. One to loop through the array and another to loop through the object.

Below is how I did it:

Note: I used console.log() as I tested in Nodejs. You may substitue for document.write() if you wish.

var lala = [
    {name: "lala", size: "lala", weight: 88},
    {name: "lala", size: "lala", weight: 88}
];

// Loop through the Array
for (var item in lala) {
  // Output Array item
 console.log('item[' + item + ']: ' + lala[item]);
  // Loop through Object
  for (var prop in lala[item]){
    // Output Object property and value
    console.log('  |- ' + prop + ": " + lala[item][prop]);
  }
}

Output is as follows:

item[0]: [object Object]
  |- name: lala
  |- size: lala
  |- weight: 88
item[1]: [object Object]
  |- name: lala
  |- size: lala
  |- weight: 88

If you have any other questions feel free to ask. :)

The lala variable > var lala = [ {name: "lala", size: "lala", weight: 88}, {name: "lala", size: "lala", weight: 88} ]; indicates the two object are wrapped by array, Since for...in... statement loop through an array and return the index, the prop in for (var prop in lala) will be its index and lala[prop] will be each object (however, MDN says "There is no guarantee that for...in will return the indexes in any particular order ........" https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in) That is, lala[0] -> {name: "lala", size: "lala", weight: 88}, lala[1]-> {name: "lala", size: "lala", weight: 88}

if you want to get the properties separately, try

for(var ele =0; ele<lala.length; ele++){
    for(prop in lala[ele]){
          document.write(prop + ":" + lala[ele][prop]);
    }
}

Hope it helps you.