如何基于条件将项目添加到数组

Question

Instead of doing a nested conditional, is there a cleaner more efficient way of achieving this:

• if option === 3, add both the nearbyLocations and recentSearches object to array
• if option == 1, add only the recentSearches
• else (or option === 2), add only nearbyLocations object

See below for my code. Thank you!

const results = option === 3 ? [...state.nearbyLocations, ...recentSearches] : option === 1 ? [...recentSearches] : [...state.nearbyLocations]

Answer 1

You could use multiple spread elements that depending on the options contribute a value to the result or not:

const results = [
    ...(option === 3 || option === 2 ? state.nearbyLocations : []),
    ...(option === 3 || option === 1 ? recentSearches : []),
];

or with bit masks - as that is what your options essentially match - do

const results = [
    ...(option & 0b10 ? state.nearbyLocations : []),
    ...(option & 0b01 ? recentSearches : []),
];

Answer 2

In this situation, it's better to use a switch statement:

var results = [];
switch (option) {
    case 3:
        results.push(...state.nearbyLocations, ...recentSearches);
        break;
    case 1:
        results.push(...recentSearches);
        break;
    case 2:
        results.push(...state.nearbyLocations);
        break;
}