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I am using mongoose (pointing to mongolab) with nodejs and when I do .findOne and get a result back, one field is an array of JSON objects but when I console.log the array I am getting

[ [object Object], [object Object], [object Object], [object Object], [object Object] ]

When I copy the exact contents of the array and manually create it and console.log it I see all the JSON. This doesn't sound like a problem, but when I try to splice this array returned, I am running into issues.

console.log(arr.splice(0, 1));

outputs

[ [object Object], [object Object], [object Object], [object Object] ]

So it is returning all of the objects that remain and not the deleted one. When I do the splice on the array I created by copying exactly what is in the array that is causing problems it works fine (the element returned is the one I deleted).

I tried going through the array in a for loop and logged each element and the JSON appeared fine. I have a workaround but shouldn't have to do this much more for it to work like it should...

    // outputs [ [object Object], [object Object]... ]
    console.log(s);

for (var i = 0; i < s.length; i++) {
    if (i == start) {
        el = s[i];
        break;
    }
}

s.splice(start, 1);
s.splice(end, 0, el);

for (var i = 0; i < s.length; i++) {
    // outputs the JSON for each element
    console.log(s[i]);
}

I also tried the array.splice example on w3schools to make sure splice worked in general and it worked fine.

var fruits = ["Banana", "Orange", "Apple", "Mango"];
console.log("Removed: " + fruits.splice(2,1,"Lemon"));
console.log(fruits);

// OUTPUTS
Removed: Apple
Banana,Orange,Lemon,Mango

I am using mongoose (pointing to mongolab) with nodejs and when I do .findOne and get a result back, one field is an array of JSON objects but when I console.log the array I am getting

[ [object Object], [object Object], [object Object], [object Object], [object Object] ]

When I copy the exact contents of the array and manually create it and console.log it I see all the JSON. This doesn't sound like a problem, but when I try to splice this array returned, I am running into issues.

console.log(arr.splice(0, 1));

outputs

[ [object Object], [object Object], [object Object], [object Object] ]

So it is returning all of the objects that remain and not the deleted one. When I do the splice on the array I created by copying exactly what is in the array that is causing problems it works fine (the element returned is the one I deleted).

I tried going through the array in a for loop and logged each element and the JSON appeared fine. I have a workaround but shouldn't have to do this much more for it to work like it should...

    // outputs [ [object Object], [object Object]... ]
    console.log(s);

for (var i = 0; i < s.length; i++) {
    if (i == start) {
        el = s[i];
        break;
    }
}

s.splice(start, 1);
s.splice(end, 0, el);

for (var i = 0; i < s.length; i++) {
    // outputs the JSON for each element
    console.log(s[i]);
}

I also tried the array.splice example on w3schools to make sure splice worked in general and it worked fine.

var fruits = ["Banana", "Orange", "Apple", "Mango"];
console.log("Removed: " + fruits.splice(2,1,"Lemon"));
console.log(fruits);

// OUTPUTS
Removed: Apple
Banana,Orange,Lemon,Mango

• javascript
• arrays
• json
• node.js
• mongoose

Share Improve this question Follow asked Jan 5, 2012 at 20:07 mattsimonismattsimonis 4111 silver badge44 bronze badges

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3 Answers 3

Sorted by: Reset to default 3

From: https://developer.mozilla/en/JavaScript/Reference/Global_Objects/Array/splice

Returns

An array containing the removed elements. If only one element is removed, an array of one element is returned

splice changes the original array. Don't print what it returns, print the array that you gave it after you called it.

arr.splice(0, 1);
console.log(arr);

I was able to figure out the issue after much frustration. It turns out the array of objects ing back was not properly set up in my schema. I needed to define an object that would be in the array, and then for that property in the schema have something like this.

var SongSchema = new Schema({
    title: String,
    url: String,
    source: String,
    duration: String
});

var PlaylistSchema = new Schema({
    userid: {
        type: String,
        index: { unique: true }
    },
    playlist_name: String,
    songs: [SongSchema]
});

Worked after that.

thanks user1123534...Your method has worked. instead of putting playlistSchema as

var PlaylistSchema = new Schema({
  userid: {
    type: String,
    index: { unique: true }
  },
  playlist_name: String,
  songs: [
    title: String,
    url: String,
    source: String,
    duration: String
  ]
});

create a new schema for embedded properties in array as in

var SongSchema = new Schema({
  title: String,
  url: String,
  source: String,
  duration: String
});

and use the above schema in playlistSchema as

var PlaylistSchema = new Schema({
  userid: {
    type: String,
    index: { unique: true }
  },
  playlist_name: String,
  songs: [SongSchema]
});

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