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

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2018-10-12 19:37:13 +00:00
---
title: Using Objects for Lookups
---
## Using Objects for Lookups
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Heres the example:
```javascript
// 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");
```
Heres a solution:
We do not change anything here:
```javascript
function phoneticLookup(val) {
var result = "";
```
We need to convert the switch statement into an object. Transfer all `case` values to object properties:
```javascript
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.
```javascript
result = lookup[val];
```
· Run code at [repl.it](https://repl.it/@AdrianSkar/Using-objects-for-lookups).
### Resources
- ["JavaScript object basics" - *MDN JavaScript reference*](https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Objects/Basics)