Filtering on nested array of objects to return the entire matching object-CodePudding

My array of nested objects looks like this along with the array to match it with

let findThis = ["Water"];
    let arrayOfElements = 
    [
            {
               "code": "a",
               "templates": [
                 {
                   "templateCode": "Water",
                   "title": "Earth"
                 },
                 {
                   "templateCode": "Milk",
                   "title": "Sky"
                 }
                 
                ]
            },
            {
               "code": "b",
               "templates": []
            },
            {
               "code": "c",
               "templates": [
                 {
                   "templateCode": "Water",
                   "title": "Earth"
                 },
                 {
                   "templateCode": "Tree",
                   "title": "Moon"
                 }
            },
            {
               "code": "d",
               "templates": [
                 {
                   "templateCode": "Tooth",
                   "title": "Tiger"
                 }
            }
    ]

I want to extract those objects whose templateCode is Water. So my final returned array should look like this.

let result = 
[
        {
           "code": "a",
           "templates": [
             {
               "templateCode": "Water",
               "title": "Earth"
             },
             {
               "templateCode": "Milk",
               "title": "Sky"
             }
             
            ]
        },
        {
           "code": "c",
           "templates": [
             {
               "templateCode": "Water",
               "title": "Earth"
             },
             {
               "templateCode": "Tree",
               "title": "Moon"
             }
        }
]

I tried:

arrayOfElements.filter(x => x.templates.filter(y => findThis.includes(y.templateCode)));

But it is returning the entire array itself and is not working.

CodePudding user response：

You need to filter the arrayOfElements with the condition of any templateCode existing inside the findThis array.

let findThis = ["Water"];
    let arrayOfElements = 
    [
            {
               "code": "a",
               "templates": [
                 {
                   "templateCode": "Water",
                   "title": "Earth"
                 },
                 {
                   "templateCode": "Milk",
                   "title": "Sky"
                 }
                 
                ]
            },
            {
               "code": "b",
               "templates": []
            },
            {
               "code": "c",
               "templates": [
                 {
                   "templateCode": "Water",
                   "title": "Earth"
                 },
                 {
                   "templateCode": "Tree",
                   "title": "Moon"
                 }
                 ]
            },
            {
               "code": "d",
               "templates": [
                 {
                   "templateCode": "Tooth",
                   "title": "Tiger"
                 }
                 ]
            }
    ]
    
const result = arrayOfElements.filter(item => item.templates.some(t => findThis.includes(t.templateCode)))

console.log(result)