1.7 KiB
Half a million
Using variables as keys
One possible and very useful way to get something from an object is using a variable value. Sometimes you don't know in advance what the key will be.
Using variables allows your code to be flexible, let's see how to do it
let greeting = 'hello'
let say = { hello: 'my friend', hoy: 'mate' }
// Here when we access it will use
console.log(say[greeting]) // -> 'my friend'
// It is exactly the same as doing
console.log(say['hello']) // -> 'my friend'
// But if we change the value of our variable:
greeting = 'hoy'
// The same code now returns another value
console.log(say[greeting]) // -> 'mate'
We are using the value
of the variable, not the identifier
to access the
property, so:
console.log(say[greeting]) // -> 'mate'
console.log(say['greeting']) // -> undefined
console.log(say.greeting) // -> undefined
// greeting is the identifier, but we use it's value, here `'hoy'`
Instructions
In this exercise, we will do a heist.
Our intel already worked the plan out and we are able to provide you with 2 variables:
- a
vault
object - a
secret
string
Your goal is to steal the secret
matching value from the vault
.
Declare a variable loot
and assign it's value using the variable secret
value as a key to access the matching value from the vault
.
You must then replace the value from the vault's secret by a message of your choice.
Example: if vault
is { '53CR37-k0D3': '1/2 MM $' }
and secret
is
'53CR37-k0D3'
:
loot
should be1/2 MM $
vault
should be{ '53CR37-k0D3': 'I stole your $$' }
I sure hope you didn't do anything stupid, Jackie.
― Ray Nicolette