how to merge two array of object in following format using javascript

Question

array1 = [{
    questionId: "5e52b55330bb2cee102b9a39",
    note: "Name",
    prefillValue: "prasanna"
},

{
    questionId: "5e52b56b30bb2cee102b9a3f",
    note: "Mobile Number",
    prefillValue: null
},
{
    questionId: "5e52b58230bb2cee102b9a42",
    note: "Agent Email",
    prefillValue: null
},
{
    questionId: "5e52b55e30bb2cee102b9a3c",
    note: "Email",
    prefillValue: null
},
{
    questionId: "5e52c39730bb2cee102b9a47",
    note: "Agent ID",
    prefillValue: null
},
{
    questionId: "5e54dbdd30bb2c6018f488ca",
    note: "Location",
    prefillValue: null
}
]


array2 = [{
    questionId: "5e52b55e30bb2cee102b9a3c",
    note: "Email",
    prefillValue: "skk@gmail.com"
},
{
    questionId: "5e52c39730bb2cee102b9a47",
    note: "Agent ID",
    prefillValue: "34"
},
{
    questionId: "5e54dbdd30bb2c6018f488ca",
    note: "Location",
    prefillValue: "Chennai"
}
]

Expected output:

array3 = [{
        questionId: "5e52b55330bb2cee102b9a39",
        note: "Name",
        prefillValue: "prasanna"
    },

    {
        questionId: "5e52b56b30bb2cee102b9a3f",
        note: "Mobile Number",
        prefillValue: null
    }, {
        questionId: "5e52b58230bb2cee102b9a42",
        note: "Agent Email",
        prefillValue: null
    }, {
        questionId: "5e52b55e30bb2cee102b9a3c",
        note: "Email",
        prefillValue: null
    }, {
        questionId: "5e52b55e30bb2cee102b9a3c",
        note: "Email",
        prefillValue: "skk@gmail.com"
    }, {
        questionId: "5e52c39730bb2cee102b9a47",
        note: "Agent ID",
        prefillValue: "34"
    },
    {
        questionId: "5e54dbdd30bb2c6018f488ca",
        note: "Location",
        prefillValue: "Chennai"
    }
]

Are you asking how to merge arrays without ending up with duplicates? — TKoL, Mar 19 '20 at 17:53

score 4 · Answer 1 · edited Mar 19 '20 at 17:57

4

let array1 = [{
    questionId: "5e52b55330bb2cee102b9a39",
    note: "Name",
    prefillValue: "prasanna"
},

{
    questionId: "5e52b56b30bb2cee102b9a3f",
    note: "Mobile Number",
    prefillValue: null
},
{
    questionId: "5e52b58230bb2cee102b9a42",
    note: "Agent Email",
    prefillValue: null
},
{
    questionId: "5e52b55e30bb2cee102b9a3c",
    note: "Email",
    prefillValue: null
},
{
    questionId: "5e52c39730bb2cee102b9a47",
    note: "Agent ID",
    prefillValue: null
},
{
    questionId: "5e54dbdd30bb2c6018f488ca",
    note: "Location",
    prefillValue: null
}
]


let array2 = [{
    questionId: "5e52b55e30bb2cee102b9a3c",
    note: "Email",
    prefillValue: "skk@gmail.com"
},
{
    questionId: "5e52c39730bb2cee102b9a47",
    note: "Agent ID",
    prefillValue: "34"
},
{
    questionId: "5e54dbdd30bb2c6018f488ca",
    note: "Location",
    prefillValue: "Chennai"
}
]

let array3 = [...array1,...array2];

console.log(array3)

edited Mar 19 '20 at 17:57

Abdullah Abid

1,541
3
10
24

answered Mar 19 '20 at 17:49

Ace

1,398
13
24

This is not an array of objects as the OP described. – Rob Moll Mar 19 '20 at 17:51
1

it should work with the object provided in the question, – Ace Mar 19 '20 at 17:54
I need to remove duplicated QuestionID from the first array – Prasanna watson Mar 19 '20 at 17:57
Then you should filter them before merging – Ace Mar 19 '20 at 17:59
Please give me one example – Prasanna watson Mar 19 '20 at 18:00
So you wanna remove duplicate `QuestionID` Objects in both array or only first one – Ace Mar 19 '20 at 18:02
1

@Prasannawatson take a look at [here](https://stackoverflow.com/a/56768137/9871756) – Abdullah Abid Mar 19 '20 at 18:05
@Badasskid only first one – Prasanna watson Mar 20 '20 at 02:12

score 1 · Accepted Answer · answered Mar 19 '20 at 18:03

You can use Object.assign to copy properties from one object to another

const array1 = [{
      questionId: "5e52b55330bb2cee102b9a39",
      note: "Name",
      prefillValue: "prasanna"
  },

  {
      questionId: "5e52b56b30bb2cee102b9a3f",
      note: "Mobile Number",
      prefillValue: null
  },
  {
      questionId: "5e52b58230bb2cee102b9a42",
      note: "Agent Email",
      prefillValue: null
  },
  {
      questionId: "5e52b55e30bb2cee102b9a3c",
      note: "Email",
      prefillValue: null
  },
  {
      questionId: "5e52c39730bb2cee102b9a47",
      note: "Agent ID",
      prefillValue: null
  },
  {
      questionId: "5e54dbdd30bb2c6018f488ca",
      note: "Location",
      prefillValue: null
  }
]


const array2 = [{
      questionId: "5e52b55e30bb2cee102b9a3c",
      note: "Email",
      prefillValue: "skk@gmail.com"
  },
  {
      questionId: "5e52c39730bb2cee102b9a47",
      note: "Agent ID",
      prefillValue: "34"
  },
  {
      questionId: "5e54dbdd30bb2c6018f488ca",
      note: "Location",
      prefillValue: "Chennai"
  }
]


const array3 = array1.map(o => Object.assign(o, array2.find(a => a.questionId === o.questionId)));

console.log(array3)

Mr Khan · Answer 3 · 2020-03-19T18:39:29.363

The filter() method creates a new array with all elements that pass the test implemented by the provided function.

You can remove duplicate keys in this way.

let array1 = [{
    questionId: "5e52b55330bb2cee102b9a39",
    note: "Name",
    prefillValue: "prasanna"
},

{
    questionId: "5e52b56b30bb2cee102b9a3f",
    note: "Mobile Number",
    prefillValue: null
},
{
    questionId: "5e52b58230bb2cee102b9a42",
    note: "Agent Email",
    prefillValue: null
},
{
    questionId: "5e52b55e30bb2cee102b9a3c",
    note: "Email",
    prefillValue: null
},
{
    questionId: "5e52c39730bb2cee102b9a47",
    note: "Agent ID",
    prefillValue: null
},
{
    questionId: "5e54dbdd30bb2c6018f488ca",
    note: "Location",
    prefillValue: null
}
]

var uniq = {}
var arrFiltered = arrays1.filter(obj => !uniq[obj.questionId] && (uniq[obj.questionId] = true));
console.log('Filtered Array:', arrFiltered)

reference can be found here

score 0 · Answer 4 · answered Mar 19 '20 at 18:12

let array1 = [{
    questionId: "5e52b55330bb2cee102b9a39",
    note: "Name",
    prefillValue: "prasanna"
},

{
    questionId: "5e52b56b30bb2cee102b9a3f",
    note: "Mobile Number",
    prefillValue: null
},
{
    questionId: "5e52b58230bb2cee102b9a42",
    note: "Agent Email",
    prefillValue: null
},
{
    questionId: "5e52b55e30bb2cee102b9a3c",
    note: "Email",
    prefillValue: null
},
{
    questionId: "5e52c39730bb2cee102b9a47",
    note: "Agent ID",
    prefillValue: null
},
{
    questionId: "5e54dbdd30bb2c6018f488ca",
    note: "Location",
    prefillValue: null
}
]


let array2 = [{
    questionId: "5e52b55e30bb2cee102b9a3c",
    note: "Email",
    prefillValue: "skk@gmail.com"
},
{
    questionId: "5e52c39730bb2cee102b9a47",
    note: "Agent ID",
    prefillValue: "34"
},
{
    questionId: "5e54dbdd30bb2c6018f488ca",
    note: "Location",
    prefillValue: "Chennai"
}
]


let array3 = array1.concat(...array2);

console.log(array3)

how to merge two array of object in following format using javascript

4 Answers4