Record Collection Exercise. Is there a way to do it by accessing the Array instead of If/Else statement?

JavaScript
1

Tell us what’s happening:

Is there a way I can do this exercise by accessing the array, instead of doing in with If/Else statement? How would that be? I was trying to do it that way before I saw the solution.

You can see I also tried to use “var collection = delete [“collection”][“2548”][“artist”][“Bon Jovi”];” I tried all of different forms but it just didn’t work. Why? If there’s a way to do that how would that be? Is it possible? If not possible, why?

Here is the Exercise: https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/record-collection

Here’s the solution with If/Else statement: https://guide.freecodecamp.org/certifications/javascript-algorithms-and-data-structures/basic-javascript/record-collection/

Your code so far


// 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) {
  
  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",
      "artist": "ABBA",
      "tracks": "Take a Chance on Me"
    }
};

 return collection
  
 var collection = delete ["collection"]["2548"]["artist"]["Bon Jovi"];

}

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

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Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/record-collection

2

You don’t need to declare “collection” inside the function. It has been already declared for you. Your code “var collection = delete [“collection”][“2548”][“artist”][“Bon Jovi”] doesn’t make sense. If you want to delete the property “artist” from id “2548” of the collection you have to write like this delete collection[“2548”][“artist”]. Note that delete something returns true or false.

3

This isn’t valid JS:

var collection = delete ["collection"]["2548"]["artist"]["Bon Jovi"];

In this case, you access properties like collection['2548']. collection is the identifier that the object is assigned to. This isn’t a thing: ['collection'].

And you can’t assign this: collection = delete {something}. delete is an operation on an object (it deletes a property), it makes no sense trying to assign it to something.

5

It put this in the code but it doesn’t work to complete the request. So, there’s no way of deleting the property by accessing the array that way, without using if/else statement?

6 
const myObj = {
 foo: 1,
 bar: 2
}

delete myObj['foo']

myObj // myObj is now { bar: 2 }

Do you mean object rather than array, or are you atually trying to delete things in the array in that object?

7

For example, the exercise asks:

“After updateRecords(1245, "tracks", "Addicted to Love") , tracks should have "Addicted to Love" as the last element.”

But when I add this code:

var collection = collection[“1245”][tracks].push

it doesn’t work.

8

For example, the exercise asks:

“After updateRecords(1245, "tracks", "Addicted to Love") , tracks should have "Addicted to Love" as the last element.”

But when I add this code:

var collection = collection[“1245”][tracks].push

it doesn’t work.

9

Again, syntax is wrong. push is a function that takes the thing you want to push into the array. myArray.push(1) pushes the value 1 into myArray.

And push, like delete, works as an operation. It returns a value, but that’s the new length of the array. So if you do adjust your code so push is correct, what you will be doing with collection = someArray.push(someValue) is overwriting collection with a number