从数组的第一个索引的 object 解构值

Question

How can I replace accessing the temp variable values from the following code extract? I have tried to get all values through the default JS code, however, I would like to use destructuring here

const temp = context.options[0]; // <----- here
const avoidPattern = [
    'foo', 'bar', 'abc', 'value', 'temp', 'num'
];


return [...avoidPattern, ...temp]

Answer 1

You might use this

 const context = { options: [1,2,3] } const [temp] = context.options; console.log(temp)

Answer 2

This can also be possible if we destructure object and array at the same time.

 const context = { options: [1, 2, 3] }; const { options: [temp] } = context; console.log(temp);

Answer 3

 let arr=['data','title','image']; let [first]=arr[1]; console.log(first);

Answer 4

An interesting that Array in JavaScript is an object, So you can destructure an array as object like this

 const context = { options: [1, 2, 3] }; const { options } = context; // [1, 2, 3] const {0:firstItem } = options; console.log(firstItem);

As you can see, key of options array is integer number. Actually, it's index. In this way, you can destructure an array with the long array by index in the that way.

More details here: Object destructuring solution for long arrays?

Answer 5

If you want to destructure the first element out of the options array.

1. You can first destructure the options property from the context object.
2. Then you can destructure the first item from the options array.

 const context = { options: [1, 2, 3] }; // Destucture the options key property const {options} = context console.log(options) // [1,2,3] // Next, destructure the first item from the array const [first] = options console.log(first) // 1

You can also combine the two steps mentioned above using the colon : operator, which is used to provide an alias while destructing an object.

 const context = { options: [1, 2, 3] }; // Destucture the options property // and in the alias destructure the first item of the array const {options: [first]} = context console.log(first) // 1