How to delete the array elements at index in firestore in javascript

Question

    var arr = [ "GKRLrcpSL2BmKx3BfvWj","fMwH404fweoFJJqyE5Nf" , "DTurwbw64CWw4WosUQtC" ] //
arr.forEach((element) => {
    console.log(element);
    db.collection("Check").doc(element).get().then((docs) => {
        var data = docs.data();
        var arr = data.fill;
        arr.forEach((item) => {
            if(item['check'] == 'a') {
                db.collection("Check").doc(element).update({
                    fill: firebase.firestore.FieldValue.arrayRemove('check')
                }).then((val)  => {console.log("Updated")})
            }
        });
    });
});

I have a collection Check which consist of an array fill and there are objects in the fill i want to match the data in the fill and delete the value that index in firestore

Doug Stevenson · Accepted Answer · 2020-06-09 06:48:16Z

4

FieldValue.arrayRemove() only works with the complete value of the array item to remove. It won't work for removing items by index. In fact, Firestore doesn't offer any way to directly modify array items by index.

What you'll have to do instead is read the document, modify the "fill" array in memory as you see fit, then update the document with the new value back to the document.

answered Jun 9, 2020 at 6:48

Doug Stevenson

321k37 gold badges458 silver badges474 bronze badges

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

Comments

l1b3rty · Accepted Answer · 2020-06-09 08:17:17Z

2

If that works for you, use a map instead of an array, putting dummy values if necessary. Then you can remove the field directly.

fill: {
  a: xxx,
  b: xxx,
  check: xxx
}

db.collection("Check").doc(element).update({
  fill.check: firebase.firestore.FieldValue.delete()
})

answered Jun 9, 2020 at 8:17

l1b3rty

3,68019 silver badges39 bronze badges

Comments

anlijudavid · Accepted Answer · 2020-12-21 00:02:35Z

-3

My solution is based on specifying the item ID to remove, example:

 firebase
        .firestore()
        .collection('projects')    // Collection
        .doc(project.id)           // ID string
        .delete()                  // Promise

answered Dec 21, 2020 at 0:02

anlijudavid

5396 silver badges13 bronze badges

Collectives™ on Stack Overflow

How to delete the array elements at index in firestore in javascript

3 Answers 3

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related