freeCodeCamp/guide/english/certifications/javascript-algorithms-and-data-structures/basic-javascript/using-objects-for-lookups/index.md

title

title
Using Objects for Lookups

Using Objects for Lookups

Here’s the example:

// Setup
function phoneticLookup(val) {
  var result = "";

  // Only change code below this line
  switch(val) {
    case "alpha": 
      result = "Adams";
      break;
    case "bravo": 
      result = "Boston";
      break;
    case "charlie": 
      result = "Chicago";
      break;
    case "delta": 
      result = "Denver";
      break;
    case "echo": 
      result = "Easy";
      break;
    case "foxtrot": 
      result = "Frank";
  }

  // Only change code above this line
  return result;
}

// Change this value to test
phoneticLookup("charlie");

Here’s a solution: We do not change anything here:

function phoneticLookup(val) {
  var result = "";

We need to convert the switch statement into an object. Transfer all case values to object properties:

function phoneticLookup(val) {
  var result = "";
  var lookup = {
    "alpha": "Adams",
    "bravo": "Boston",
    "charlie": "Chicago",
    "delta": "Denver",
    "echo": "Easy",
    "foxtrot": "Frank"
  };

After converting our case statements into object properties you can make use of the variable result to let the function return the correct value.

  result = lookup[val];

· Run code at repl.it.

Resources

• "JavaScript object basics" - MDN JavaScript reference