how to do a list with array?

Question

I have an array that contains several anime characters, and I am using a db to store which ones you have like this:

var your_chars = '2,5,7,93'

u have the chars with this numbers! json/array:

"all_units":[
        {
            "name":"",
            "anime":"",
            "star":"0",
            "image":""    
        },
        {
            "name":"Naruto Uzumaki",
            "anime":"Naruto",
            "star":"2",
            "image":""
        },
        {
            "name":"Son Goku",
            "anime":"Dragon Ball",
            "star":"2",
            "image":""
        },
        {
            "name":"Monkey D. Luffy",
            "anime":"One Piece",
            "star":"2",
            "image":""
        },
        {
            "name":"Naruto Uzumaki (Sage Mode)",
            "anime":"Naruto",
            "star":"4",
            "image":""        
        }
    ]

so if u have char 2, u have naruto uzumaki. but I want to make a list of all units you have (being possible to see name and stars) like this:

[2] - Son Goku (2)
[4] - Naruto Uzumaki Sage (4)

[{numer in array}] - {name} - ({stars})

I tried it using 'for(){}' but I didn't get much result :(

summarizing my goal: make a list of chars I own (var in your_chars) and print it

my last try:

(async()=>{
        var fs = require('fs');
        var item = JSON.parse(fs.readFileSync("./utils/itens.json", "utf-8"));//heres json archive
        
        let u = await client.db.get("main", "charsOwned_{user ID}");//this returns: "value":"2,5,6,1" 
        let chars = u.value
        let list = ''
        for(i = 0; i < 30;i++){
            if(chars[i]){
            let c = item.all_units[i].name
            let n_s = item.all_units[i].star
            let s = '<:s_:813141250911633438>';

            list = list + `\n**[\${i}]**・\${c} \${s.repeat(n_s)}`
            }
        }
        console.log(lista)

})()

Answer 1

It's a simple one-liner:

let mychars = your_chars.split(',').map(n => json.all_units.length>=+n+1 ? json.all_units[+n].name : "").filter(e=>e);

Here it is, broken out with comments

let mychars = your_chars.split(',') 
              // take your list and turn it into an array
               .map(n => json.all_units.length>=+n+1 ? json.all_units[+n].name : "") 
               // map lets us take an array, item by item, manipulate that however we want, and then return it to be the new item in that array
               // this makes sure the number (turned into a number with the +) index exists in your all_data array. If so, return the name, if not return ''
               .filter(e=>e);
               // filter out the empties because (in this case) we're asking it to find index 93, which doesn't exist and will cause an empty array item for us. Filter takes that out.

Note: the array indexes start at zero, and I treated your_chars as actual indexes. If those are not zero-based, let me know and I can adjust this code

var your_chars = '1,4,7,93'

let json = {
  "all_units": [{
      "name": "",
      "anime": "",
      "star": "0",
      "image": ""
    },
    {
      "name": "Naruto Uzumaki",
      "anime": "Naruto",
      "star": "2",
      "image": ""
    },
    {
      "name": "Son Goku",
      "anime": "Dragon Ball",
      "star": "2",
      "image": ""
    },
    {
      "name": "Monkey D. Luffy",
      "anime": "One Piece",
      "star": "2",
      "image": ""
    },
    {
      "name": "Naruto Uzumaki (Sage Mode)",
      "anime": "Naruto",
      "star": "4",
      "image": ""
    }
  ]
}
let mychars = your_chars.split(',').map(n => json.all_units.length>=+n+1 ? json.all_units[+n].name : "").filter(e=>e);
console.log(mychars)

Answer 2

Assuming your_chars holds a value like '2,4,9,99'

 const response = 
        your_chars.split(',')
                  .map(i => ({...all_units[i], position: i}))
                  .filter(({position}) => position < all_units.length)
                  .map(({name, star, position}) => `[${position}] - ${name} (${star})`)

console.log(response);
//  ["[2] - Son Goku (2)", "[4] - Naruto Uzumaki (Sage Mode) (4)"]

You can print a single string with:

console.log(response.join(' '));

Answer 3

I agree with FMoosavi's answer but it can be done in a different way using filter.

I would have done it like so:

const all_units = [
        {
            "name":"",
            "anime":"",
            "star":"0",
            "image":""    
        },
        {
            "name":"Naruto Uzumaki",
            "anime":"Naruto",
            "star":"2",
            "image":""
        },
        {
            "name":"Son Goku",
            "anime":"Dragon Ball",
            "star":"2",
            "image":""
        },
        {
            "name":"Monkey D. Luffy",
            "anime":"One Piece",
            "star":"2",
            "image":""
        },
        {
            "name":"Naruto Uzumaki (Sage Mode)",
            "anime":"Naruto",
            "star":"4",
            "image":""        
        }
    ];

// We choose chars: Naruto Uzamaki & and Naruto Uzamaki (Sage Mode):
const your_chars = "1,4";

// Split chars into array to get the indices:
const your_char_indices = your_chars.split(",").map((n) => parseInt(n));

// Then filter out your chars to get only the ones you want:
const units = all_units.filter((unit, index) => your_char_indices.includes(index));

// Then finally map into the style you want:
const result = units.map((unit, index) => `[${your_char_indices[index]}] - ${unit.name} - (${unit.star})`);

// Return the result here:
console.log(result)

Answer 4

First, you have to make an array of your chars. The following will split them to a string array. The "map" will cast them to integer:

var your_char_array = your_chars.split(',').map(parseInt);

Second, assume all_units is stored in the var named all_units. Then do this to get your result:

const finalArray=[];
all_units.forEach((unit,index)=>{
    if(your_char_array.includes(index+1)){
        finalArray.push('['+(index+1)+'] -'+unit.name+' ('+unit.star+')');
    }
})
console.log(finalArray);