When declaring an object, the names of its properties can be taken from variables. Such properties are called computed. Let's see how it's done. Let's have the following object:
let obj = {
a: 1,
b: 2,
c: 3
};
Let the name of some property be stored in a variable:
let key = 'a';
Let's make it such a way that instead of the property name, the value from our variable is taken. To do this, the variable should be enclosed in square brackets:
let obj = {
[key]: 1,
b: 2,
c: 3
};
When declaring computed properties, you can execute some code. An example:
let obj = {
[key + '1']: 1,
[key + '2']: 2,
[key + '3']: 3
};
In the following code, the key should have been taken from a variable. Fix the mistake you made:
let key = 'x';
let obj = {
key: 1,
y: 2,
z: 3
};
Given an object:
let obj = {
x: 1,
y: 2,
z: 3
};
Given variables:
let key1 = 'x';
let key2 = 'y';
let key3 = 'z';
Make the object keys to be taken from these variables.