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Javascript – Get the names in sequence from the mentioned object

I need all the names in an array from the mentioned object in sequence.

For Example:
const array = ["Menu 1","Menu 2","Menu 3","Menu 4","Menu 5","Menu 6"];

const array = [];

var obj = [
            {
                "name": "Menu 1",
                "link": "link 1",
                "subitems": [
                    {
                        "name": "Menu 2",
                        "link": "link 2",
                    }
                ]
            },
            {
                "name": "Menu 3",
                "link": "link 3",
                "subitems": [
                    {
                        "name": "Menu 4",
                        "link": "link 4",
                        "subitems": [
                            {
                                "name": "Menu 5",
                                "link": "link 5",
                            },
                            {
                                "name": "Menu 6",
                                "link": "link 6",
                            }
                        ]
                    }
                ]
            },
        ];

With recursive method I am able to get first level Menu items name, but I need all children menu items name is sequence.

function menuItems(obj) {
            if (!Array.isArray(obj)) {
                console.log('Array :>> ', obj);
            }
            else {
                for (let subdep of Object.values(obj)) {
                    menuItems(subdep);
                }
            }
        }

        menuItems(obj);

Please suggest which approach is better. Recursion or any other loop method?

Tags:

2

Answers


  1. 0

    For your purposes recursion is probably the best solution. Just make sure that you save the name values somewhere, and exit the function when all paths are exhausted.

    const arr=[{name:"Menu 1",link:"link 1",subitems:[{name:"Menu 2",link:"link 2"}]},{name:"Menu 3",link:"link 3",subitems:[{name:"Menu 4",link:"link 4",subitems:[{name:"Menu 5",link:"link 5"},{name:"Menu 6",link:"link 6"}]}]}];

// Pass in the data and initialise a output array
function menuItems(arr, out = []) {

  // Iterate over the data. If it has a name prop add its
  // value to the output array. If it has a subitems array
  // pass that array, and the output array, back into the function
  for (let obj of arr) {
    if (obj.hasOwnProperty('name')) out.push(obj.name);
    if (obj.hasOwnProperty('subitems')) menuItems(obj.subitems, out);
  }
 
 // Return the output array 
 return out;
}

console.log(menuItems(arr));
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  2. 0

    I’d suggest using a generator for this. This is a lazy solution, which can be interesting when you want to stop the iteration early and not waste memory on retrieving all the rest:

    function* menuItems(arr) {
    for (const {name, subitems} of arr) {
        if (name !== undefined) yield name;
        if (Array.isArray(subitems)) yield* menuItems(subitems);
    }
}

// Example run: fetching all
const arr = [{name:"Menu 1",link:"link 1",subitems:[{name:"Menu 2",link:"link 2"}]},{name:"Menu 3",link:"link 3",subitems:[{name:"Menu 4",link:"link 4",subitems:[{name:"Menu 5",link:"link 5"},{name:"Menu 6",link:"link 6"}]}]}];
const names = [...menuItems(arr)];
console.log(names);
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