Javascript Objects

Dot vs. bracket notation

Cannot use dot notation with variables

If  'dog' is a variable:
Attempting to lookup obj.dog will actually just look for the string value of 'dog' within our object instead of using the variables value. 

 Problem under FCC:

Basic JavaScript: Record Collection
// Setup
var collection = {
"2548": {
"album": "Slippery When Wet",
"artist": "Bon Jovi",
"tracks": [
"Let It Rock",
"You Give Love a Bad Name"
]
},
"2468": {
"album": "1999",
"artist": "Prince",
"tracks": [
"1999",
"Little Red Corvette"
]
},
"1245": {
"artist": "Robert Palmer",
"tracks": [ ]
},
"5439": {
"album": "ABBA Gold"
}
};
// Keep a copy of the collection for tests
var collectionCopy = JSON.parse(JSON.stringify(collection));

// Only change code below this line
function updateRecords(id, prop, value) {
if (value === "") {
delete collection[id][prop];
}
else if (prop === "tracks" && collection[id][prop] === undefined) {
collection[id][prop] = [];
collection[id][prop].push(value);
}
else if (Object.keys(collection[id]).includes(prop) === false) {
collection[id][prop] = value;
}
else if (prop === "tracks" && collection[id][prop][value] !== "") {
collection[id][prop].push(value);
}
else {collection[id][prop] = value};
return collection;
}

// Alter values below to test your code
updateRecords(5439, "artist", "ABBA");

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