---
url: https://gudhub.com/uk/docs/utils/merge-objects/
title: "Merge Objects\n                #"
description: "This is a method that is called to merge different objects. It allows to connect the object with the source one so that it can be changed from the source. merge"
lang: uk
updated: 2026-09-11T20:35:27.886Z
---

# Merge Objects [#](https://gudhub.com/uk/docs/utils/merge-objects/#merge-objects)

This is a method that is called to merge different objects. It allows to connect the object with the source one so that it can be changed from the source.

**mergeObjects** accepts two arguments. They can pass either the single object or array of object:

| Name | Type | Description |
| :-- | :-- | :-- |
| target | `object` | _object that will be updated_ |
| source | `object` | _object from which the data will be taken to update_ |

As a result, the target object is updated, but the source object is not changed. Properties from source object that do not exist in target one will be created there.

## Merge the Single Objects [#](https://gudhub.com/uk/docs/utils/merge-objects/#merge-the-single-objects)

In this situation we pass two objects as arguments target and source:

Копіювати

```js
import GudHub from '@gudhub/core';
const gudhub = await new GudHub();

let target = {
  name: {
    first_name: "John",
    last_name: "Dow",
  },
  gender: "Male",
  shopping_list: ["pants", "shirt"],
};

let source = {
  name: {
    first_name: "Jeremy",
    last_name: "Gordon",
  },
  gender: "Male",
  shopping_list: ["shoes", "pants"],
};


let mergedObjects = gudhub.mergeObjects(target, source)

console.log(mergedObjects)
```

As a result, we get one updated object:

Копіювати

```json
{
  "name": {
    "first_name": "Jeremy",
    "last_name": "Gordon",
  },
  "gender": "Male",
  "shopping_list": ["shoes", "shirt", "pants"],
}
```

## Merge Arrays of Objects [#](https://gudhub.com/uk/docs/utils/merge-objects/#merge-arrays-of-objects)

In case, when we pass arrays as arguments, we can take equal arrays or not.

### Equal Number of Objects [#](https://gudhub.com/uk/docs/utils/merge-objects/#equal-number-of-objects)

In this example we have arrays with two objects in each of them. Target objects will be merge with source object by their index in array:

Копіювати

```js
import GudHub from '@gudhub/core';
const gudhub = await new GudHub();

let target = [{
    // index: 0
    name: {
        first_name: "John",
        last_name: "Dow",
    },
    gender: "Male",
    shopping_list: ["pants", "shirt"],
},
{
    // index: 1
    name: {
        first_name: "Jeremy",
        last_name: "Gordon",
    },
    gender: "Male",
    shopping_list: ["shoes", "pants"],
}];

let source = [{
    // index: 0
    name:{
        last_name: "Owl",
    },
    shopping_list: ["hat", "coat"],
    orders_number: 3,
},
{
    // index: 1
    name: {
        first_name: "Johana",
        last_name: "Dow",
    },
    gender: "Female",
    shopping_list: ["skirt"]
}];


let mergedObjects = gudhub.mergeObjects(target, source)

console.log(mergedObjects)
```

In result we get :

Копіювати

```json
[
  {
    "name": { 
        "first_name": "John", 
        "last_name": "Owl" },
    "gender": "Male",
    "shopping_list": [ "pants", "shirt", "hat", "coat" ],
    "orders_number": 3
  },
  {
    "name": { 
        "first_name": "Johana", 
        "last_name": "Dow"
        },
    "gender": "Female",
    "shopping_list": [ "shoes", "pants", "skirt" ]
  }
]
```

### Source Has More Objects [#](https://gudhub.com/uk/docs/utils/merge-objects/#source-has-more-objects)

In this case, the first target object will be merge with the first one from source array and the second one from source will be added to target:

Копіювати

```js
import GudHub from '@gudhub/core';
const gudhub = await new GudHub();

let target = [{
    name: {
        first_name: "Jeremy",
        last_name: "Gordon",
    },
    gender: "Male",
    shopping_list: ["shoes", "pants"],
}];

let source = [{
    name:{
        last_name: "Owl",
    },
    shopping_list: ["hat", "coat"],
    orders_number: 3,
},
{
    name: {
        first_name: "Johana",
        last_name: "Dow",
    },
    gender: "Female",
    shopping_list: ["skirt"]
}];


let mergedObjects = gudhub.mergeObjects(target, source)

console.log(mergedObjects)
```

As a result we will get target array with two objects:

Копіювати

```json
[
  {
    "name": { 
        "first_name": "Jeremy", 
        "last_name": "Owl" 
        },
    "gender": "Male",
    "shopping_list": [ "shoes", "pants", "hat", "coat" ],
    "orders_number": 3
  },
  {
    "name": { 
        "first_name": "Johana", 
        "last_name": "Dow" 
        },
    "gender": "Female",
    "shopping_list": [ "skirt" ]
  }
]
```

> The result is the same if you pass an object instead of an array to target.

### Target Has More Objects [#](https://gudhub.com/uk/docs/utils/merge-objects/#target-has-more-objects)

In following example, the first target object is merged with the object from source array. The second will remain unchanged:

Копіювати

```js
import GudHub from '@gudhub/core';
const gudhub = await new GudHub();

let target = [{
    name: {
        first_name: "John",
        last_name: "Dow",
    },
    gender: "Male",
    shopping_list: ["pants", "shirt"],
},
{
    name: {
        first_name: "Jeremy",
        last_name: "Gordon",
    },
    gender: "Male",
    shopping_list: ["shoes", "pants"],
}];

let source = [{
    name: {
        first_name: "Johana",
        last_name: "Dow",
    },
    gender: "Female",
    shopping_list: ["skirt"]
}];


let mergedObjects = gudhub.mergeObjects(target, source)

console.log(mergedObjects)
```

Predictably, we get an array:

Копіювати

```json
[
  {
    "name": { 
        "first_name": "Johana", 
        "last_name": "Dow"
        },
    "gender": "Female",
    "shopping_list": [ "pants", "shirt", "skirt" ]
  },
  {
    "name": { 
        "first_name": "Jeremy", 
        "last_name": "Gordon" 
        },
    "gender": "Male",
    "shopping_list": [ "shoes", "pants" ]
  }
]
```

## Merge Different Argument Types [#](https://gudhub.com/uk/docs/utils/merge-objects/#merge-different-argument-types)

As mentioned above, when we have a source array and a target object, the result is an array sam to the [case with arrays](#source-has-more-objects).

The opposite situation (target array and source object) returns the object whose first properties are a target array objects. Others are properties of the source object:

Копіювати

```js
import GudHub from '@gudhub/core';
const gudhub = await new GudHub();

let target = [{
  name: {
    first_name: "John",
    last_name: "Dow",
  },
  gender: "Male",
  shopping_list: ["pants", "shirt"],
},
{
  name: {
    first_name: "Jeremy",
    last_name: "Gordon",
  },
  gender: "Male",
  shopping_list: ["shoes", "pants"],
}];

let source = {
  name: {
      first_name: "Johana",
      last_name: "Dow",
  },
  gender: "Female",
  shopping_list: ["skirt"]
};


let mergedObjects = gudhub.mergeObjects(target, source)

console.log(mergedObjects)
```

Копіювати

```json
{
  "0": {
    "name": { 
        "first_name": "John", 
        "last_name": "Dow" 
        },
    "gender": "Male",
    "shopping_list": [ "pants", "shirt" ]
  },
  "1": {
    "name": { 
        "first_name": "Jeremy", 
        "last_name": "Gordon" 
        },
    "gender": "Male",
    "shopping_list": [ "shoes", "pants" ]
  },
  "name": { 
      "first_name": "Johana", 
      "last_name": "Dow" 
      },
  "gender": "Female",
  "shopping_list": [ "skirt" ]
}
```

## Merge By ID [#](https://gudhub.com/uk/docs/utils/merge-objects/#merge-by-id)

As we know, utils usually are used with another methods. For example, it is used for updating items in application. In this case we can pass only the item ID to target:

Копіювати

```js
import GudHub from '@gudhub/core';
const AUTHKEY =  "KJGJsbjafskajlkmoiwuehyugT//ssefiooqw938u9jiuiOIsasdHIBSpwi20kd79uiohdwg2y81y";
const gudhub = await new GudHub(AUTHKEY);
const APPID = "27823";

let source = {
  "fields": [{
      "field_id": 645887,
      "field_value": "Dow",
      },
      {
      "field_id": 645888,
      "field_value": "John",
      }
    ],
};

let target = {
  "item_id": 2987986,
};


let mergedObjects = gudhub.mergeObjects(target, source)

// add object as an item in the application
gudhub.updateItems(APPID, mergedObjects)

console.log(mergedObjects)
```

And as a result, we get an updated item:

Копіювати

```json
{
  "item_id": 2987986,
  "fields": [{ 
        "field_id": 645887, 
        "field_value": "Dow" 
        },
    { 
        "field_id": 645888, 
        "field_value": "John" 
        }]
}
```