Find and remove inner array values in javascript

Question

I have one nested array. I need to find and remove from inner array values.

mainArray = [
        {
            name:"name1",
            idArray:["1", "2", "3"]
        }
        {
            name:"name1",
            idArray:["1", "2", "3", "5", "2"]
        }
        {
            name:"name1",
            idArray:["1", "2", "3", "4"]
        }
    ]

I need a answer like below:

mainArray = [
        {
            name:"name1",
            idArray:["1", "3"]
        }
        {
            name:"name1",
            idArray:["1", "3", "5"]
        }
        {
            name:"name1",
            idArray:["1", "3", "4"]
        }
    ]

That mean I want remove values from idArray which is id as "2". Can you give me a answer from lodas, it's more comfort.

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Eddie · Accepted Answer · 2018-04-10T13:06:18.537

1

You can map to loop thru the array. Clone each element and use filter the idArray

let mainArray = [{
    name: "name1",
    idArray: ["1", "2", "3"]
  },
  {
    name: "name1",
    idArray: ["1", "2", "3", "5", "2"]
  },
  {
    name: "name1",
    idArray: ["1", "2", "3", "4"]
  }
];

let toRemove = '2';

let result = mainArray.map(o => {
  o = Object.assign({}, o); //To clone the obj. Will not affect the original array
  o.idArray = o.idArray.filter(v => v !== toRemove);
  return o;
});

console.log(result);

Add reduce to remove the empty idArray

let mainArray = [{
    name: "name1",
    idArray: ["1", "2", "3"]
  },
  {
    name: "name1",
    idArray: ["1", "2", "3", "5", "2"]
  },
  {
    name: "name-removed",
    idArray: ["2"]
  },
  {
    name: "name1",
    idArray: ["1", "2", "3", "4"]
  },
  {
    name: "name-removed",
    idArray: []
  }
];

let toRemove = '2';

let result = mainArray.reduce((c, o) => {
  o = Object.assign({}, o);
  o.idArray = o.idArray.filter(v => v !== toRemove);
  if (o.idArray.length) c.push(o);
  return c;
}, []);

console.log(result);

edited Apr 10 '18 at 13:06

answered Apr 10 '18 at 12:36

Eddie

25,279
6
26
53

Thanks dude!.. I need one more help, That idArray is empty. Which object need to remove totally! How? – vijayaganth Apr 10 '18 at 12:55
What do you mean by remove the whole `{name: "name1",idArray: ["1", "2", "3", "4"]}` or just the `idArray` @vijayaganth – Eddie Apr 10 '18 at 12:56
whole object thing @Eddie – vijayaganth Apr 10 '18 at 12:57
What if `{name: "name1",idArray: ["2"]}`, should this be removed? @vijayaganth – Eddie Apr 10 '18 at 13:02
yeah exactly @Eddie – vijayaganth Apr 10 '18 at 13:04
Updated the post @vijayaganth – Eddie Apr 10 '18 at 13:09
Happy to help :) – Eddie Apr 10 '18 at 13:10

score 0 · Answer 2 · answered Apr 10 '18 at 12:31

Using lodash could be complex to understand the logic behind the operation. This can be achieved using simple JavaScript as below:

var removeVal = '2';
var mainArray = [
    {
        name:"name1",
        idArray:["1", "2", "3"]
    },
    {
        name:"name1",
        idArray:["1", "2", "3", "5", "2"]
    },
    {
        name:"name1",
        idArray:["1", "2", "3", "4"]
    }
];

mainArray.forEach(function(obj){
  var index = obj.idArray.indexOf(removeVal);
  if(index !== -1 ){
   obj.idArray.splice(index, 1);
  }
});

console.log(mainArray);

score 0 · Answer 3 · answered Apr 10 '18 at 12:38

0

Check out this link: remove an element of an array and resize it They use splice to remove an element an array and resize. Try using this with a multidimensional array. This how I think it should work for your problem mainArray[0].splice(2,3).

answered Apr 10 '18 at 12:38

Raph

1

score 0 · Answer 4 · answered Apr 10 '18 at 12:39

Iterate the array mainArray and find the unique values from idArray array

mainArray.forEach(function(data){
  data.idArray = findUnique(data.idArray)
});
console.log(mainArray);

function findUnique(a){
return a.filter(function(value){ return a.filter(function(val){ return val === value}).length === 1});
}

Find and remove inner array values in javascript

4 Answers4