let FCC_User = {The above code defines an object called
username: 'awesome_coder',
followers: 572,
points: 1741,
completedProjects: 15
};
FCC_User
that has four properties, each of which map to a specific value. If we wanted to know the number of followers
FCC_User
has, we can access that property by writing:
let userData = FCC_User.followers;This is called dot notation. Alternatively, we can also access the property with brackets, like so:
// userData equals 572
let userData = FCC_User['followers']Notice that with bracket notation, we enclosed
// userData equals 572
followers
in quotes. This is because the brackets actually allow us to pass a variable in to be evaluated as a property name (hint: keep this in mind for later!). Had we passed followers
in without the quotes, the JavaScript engine would have attempted to evaluate it as a variable, and a ReferenceError: followers is not defined
would have been thrown.
foods
object with three entries. Add three more entries: bananas
with a value of 13
, grapes
with a value of 35
, and strawberries
with a value of 27
.
foods
is an object
testString: 'assert(typeof foods === "object", "foods
is an object");'
- text: The foods
object has a key "bananas"
with a value of 13
testString: 'assert(foods.bananas === 13, "The foods
object has a key "bananas"
with a value of 13
");'
- text: The foods
object has a key "grapes"
with a value of 35
testString: 'assert(foods.grapes === 35, "The foods
object has a key "grapes"
with a value of 35
");'
- text: The foods
object has a key "strawberries"
with a value of 27
testString: 'assert(foods.strawberries === 27, "The foods
object has a key "strawberries"
with a value of 27
");'
- text: The key-value pairs should be set using dot or bracket notation
testString: 'assert(code.search(/bananas:/) === -1 && code.search(/grapes:/) === -1 && code.search(/strawberries:/) === -1, "The key-value pairs should be set using dot or bracket notation");'
```