CODEWITHSUNDEEP
javascript
rsteen76
rsteen76

Reputation: 75

Accessing data in an array

I have been looking at this and reading for a while but can't seem to understand. I am sure it is simple but I can not figure out why I can access the data in collection. I get an error of

test undefined

If I move outside of the for loop I can access it just fine. I am obviously missing something simple. Any help would be great.

function whatIsInAName(collection, source) {
  // What's in a name?
  var arr = [];
  // Only change ode below this line
  var test = Object.values(source);

  for(var i = 0; i < collection.length; i++) {
    if (collection[i].test === source[0].test){
      arr[i] = collection[i];
    }
  }

  // Only change code above this line
  //arr = collection[0].last;
  return arr; 
}

whatIsInAName([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", 
last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" });

Upvotes: 0

Views: 84

Answers (3)

Hedin
Hedin

Reputation: 109

try this.

function whatIsInAName(collection, source) {
  var arr = [];
  var keys = Object.keys(source);

  for(var i = 0; i < collection.length; i++) {
      var item = collection[i];
      var all = true;
      for(var k = 0; k < keys.length; k++){
          var key = keys[k];
          if(item[key] != source[key]){
            all = false;
            break;
          }
      }
      if(all){
          arr.push(item)
      }
  }

  return arr; 
}

Upvotes: 0

Ethan22
Ethan22

Reputation: 747

The objects you're passing in have no key named test. If you're trying to use the variable you created here var test = Object.values(source);, this won't work because test is an array anyways.

You could try something like: 

if (collection[i][test] === source[0][test])

but I don't think that will work either because test should have the value of Capulet according to documentation for Object.values()

Upvotes: 0

Ayush Sharma
Ayush Sharma

Reputation: 2107

In your code Object.values returning the value of source that is "Capulet", whereas in for loop you are equating source as an array(source is object), that is why, test is undefined

function whatIsInAName(collection, source) {
  // What's in a name?
  var arr = [];
  // Only change ode below this line
  
  
  var test = Object.keys(source);//changes values to keys
  console.log(test);
  for(var i = 0; i < collection.length; i++) {
    if (collection[i][test] === source[test]){ //change how you are accessing test
      arr.push(collection[i]);
    }
  }

  // Only change code above this line
  //arr = collection[0].last;
  console.log(arr);
  return arr; 
}

whatIsInAName([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", 
last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" });

Upvotes: 1

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