How to merge multiple arrays of data from firebase into a single array using js?

Question

Here I'm getting multiple array data dynamically from firebase database. I am getting like this:

[Array(2)]
   0:"php",
   1:"-kyzencds1"
 [Array(2)]
   0:"html",
   1:"-kyzssencdsd"

How to merge into a single array?

array[
    0:"php",
    1:"-kyzencds1",
    2:"html",
    3:"-kyzssencdsd"
   ]

Below is my code:

    var tags = myFirebased.ref().child('tags');
    tags.on("child_added", function(snapshot) {
        var tagkeys = snapshot.key;
        var tagName = snapshot.child("tagname").val();

     var myObj = {
        name: tagName,
        keys:tagkeys,
     };
    let array = [];
     var arr = Object.keys(myObj).map(function(k) { return myObj[k] });
     array.push(arr); 

      console.log(Array.prototype.concat(array));

Johan Willfred · Answer 1 · 2017-04-04T12:54:41.663

0

https://lodash.com/docs/4.17.4#concat or just use var arrTotal=arr1.concat(arr2)

//added for example

var tags = myFirebased.ref().child('tags');
var allTags = ['php', 'kyzencds1'];
tags.on("child_added", function (snapshot) {
    //some actions
    var receivedTags = ["html", "-kyzssencdsd"]; // This new tags right ?
    if (Array.isArray(receivedTags) && receivedTags.length) {
        allTags = allTags.concat(receivedTags); 
    }
});

edited Apr 04 '17 at 12:54

answered Apr 04 '17 at 12:28

Johan Willfred

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the array information is coming dynamically from database then how can i concat like this var arrTotal=arr1.concat(arr2).can you help me – Raj Karanam Apr 04 '17 at 12:30
Hmm, is this possible to create array on top level, for example after `var tags` and on 'child_added' just add data to you array ? – Johan Willfred Apr 04 '17 at 12:33
when I add tagkeys for array I am getting first tag only – Raj Karanam Apr 04 '17 at 12:37
Please, show me where you where are all of your tags ? (what variable contains your first array ) And where is your received information ready to merge (second array). – Johan Willfred Apr 04 '17 at 12:46
Added scratch to answer. Or I did not understand you again ? – Johan Willfred Apr 04 '17 at 12:53

How to merge multiple arrays of data from firebase into a single array using js?

1 Answers1