Remove empty element from array

Question

I am getting values as input and pushing them as an Array to the back end. There are 6 predefined items in the Array in the front end. If I send 6 values there won't be any empty elements inside the array. If I send less than 6 it's creating an empty element. That's a known fact. Now I want to filter out the empty elements before pushing the array.

Actual output

[
    {

        "ABC_Info": {
            "_id": "5c404e2d16e42513905189a1",
            "ABC": [
                {
                    "_id": "5c404e2d16e42513905189a7",
                    "a": "Dosa",
                    "b": 15,
                    "c": 30
                },
                {
                    "_id": "5c404e2d16e42513905189a6",
                    "a": "Idly",
                    "b": 25,
                    "b": 25
                },
                {
                    "_id": "5c404e2d16e42513905189a5",
                    "a": "Vada",
                    "b": 25,
                    "c": 35
                },
                {
                    "_id": "5c404e2d16e42513905189a4"
                },
                {
                    "_id": "5c404e2d16e42513905189a3"
                },
                {
                    "_id": "5c404e2d16e42513905189a2"
                }
            ]
        }
    }
]

TS

this.abcService.addabc(ABC).subscribe(
    res => {
        this.abcArray.push(res); //abcArray is a array. Before Pushing  I want to check for empty element and remove before pushing

    },
    error => console.log(error)
);
}

I have one question, what do you want to filter before pushing, do you want to check for res object and validate and push only if it is valid. Or you want to filter this.abcArray and push in filtered array? — Ashish
– Ashish, Commented Jan 17, 2019 at 12:11

Qortex · Accepted Answer · 2019-01-17 10:35:42Z

3

You need to use the filter method on your array if you'd like to make it after you have the data:

this.abcArray.filter(item => ...your predicate to say an item is non-empty...)

If you can control when the items are pushed or not, why don't you simply push them just when you know they are non-empty?

if (... your predicate non empty ...)
  this.abcArray.push(res)

answered Jan 17, 2019 at 10:35

Qortex

7,5124 gold badges46 silver badges62 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Christian Vincenzo Traina · Accepted Answer · 2019-01-17 15:40:52Z

2

You want to know if the object is empty besides the _id property, so you can do something like this:

res.ABC.filter(obj => {
  const keys = Object.keys(obj);
  return (keys.length !== 1  || keys[0] !== '_id') && keys.length !== 0;
});

edited Jan 17, 2019 at 15:40

answered Jan 17, 2019 at 11:06

Christian Vincenzo Traina

10.6k4 gold badges45 silver badges79 bronze badges

1 Comment

Sidhu Tesingu Over a year ago

thanks. I could get empty objects that besides _id. How to remove that and push only those with values

sreejithsdev · Accepted Answer · 2019-01-22 09:18:07Z

1

You can use filter method and filter array based on property count in each item like follows

this.abcService.addabc(ABC).subscribe(
    res => {
        let res1 = res.filter(i=>Object.keys(i.ABC_Info.ABC).length >1);
        this.abcArray.push(res1); //abcArray is a array. Before Pushing  I want to check for empty element and remove before pushing

    },
    error => console.log(error)
);
}

filter array element without any property like _id you can use

res.filter(i=>Object.keys(i.ABC_Info.ABC).length >0);

edited Jan 22, 2019 at 9:18

answered Jan 17, 2019 at 11:01

sreejithsdev

1,21012 silver badges26 bronze badges

2 Comments

Sidhu Tesingu Over a year ago

but this taking off my object names

sreejithsdev Over a year ago

you could try this way res.filter(i=>Object.keys(i.ABC_Info.ABC).length >1);

lovis91 · Accepted Answer · 2019-01-17 10:42:25Z

1

You can use array filter :

this.abcArray = res.ABC.filter(result => result.a && result.b && result.c);

edited Jan 17, 2019 at 10:42

answered Jan 17, 2019 at 10:34

lovis91

2,1692 gold badges16 silver badges26 bronze badges

Collectives™ on Stack Overflow

Remove empty element from array

4 Answers 4

Comments

1 Comment

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

1 Comment

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related