How to transform object in array to create multiples of it's own if object value is an array

user_5357384 0
Viewed 44

I have an array of objects which have the same structure except that some values have arrays as the type to signify that it has multiple values. I need to create a new object in that array based on how many items in the array.

const arrayOfObjects = [
  {
      "Serial Number": "83675327350061093222581609820467",
      "Part Number": "LJ98-10C779-AA",
      "Cell Count": "32",
      "Length": "6"
  },
  {
      "Serial Number": "19584757350061093222581606739916",
      "Type": "Extended Range",
      "Part Number": "SW23",
      "Length": "50"
  },
  {
      "Serial Number": [
          "90946117350061093222581604839920",
          "77362117350061093222581604891733",
          "77362117350061093222581604891734",
      ],
      "Part Number": [
          "TR40-60C779-AA",
          "ST41-60C780-AA",
          "ZT41-60C780-AA",
      ],
      "Cell Count": [
          "28",
          "27",
          "26"
      ],
      "Length": [
          "10",
          "11",
          "12"
      ]
  }
]

Below is how i want to transform it

const transformedArray = [
  {
      "Serial Number": "83675327350061093222581609820467",
      "Part Number": "LJ98-10C779-AA",
      "Cell Count": "32",
      "Length": "6"
  },
  {
      "Serial Number": "19584757350061093222581606739916",
      "Type": "Extended Range",
      "Part Number": "SW23",
      "Length": "50"
  },
   {
      "Serial Number": "90946117350061093222581604839920",
      "Part Number": "TR40-60C779-AA",
       "Cell Count": "28",
      "Length": "10"
  },
  {
      "Serial Number": "77362117350061093222581604891733",
      "Part Number": "ST41-60C780-AA",
      "Cell Count": "27",
      "Length": "11"
  },
  {
    "Serial Number": "77362117350061093222581604891734",
    "Part Number": "ZT41-60C780-AA",
    "Cell Count": "26",
    "Length": "12"
  },
]

I have tried to solve it with the below code attempt, please help complete:

let newItemsArray = [];

arrayOfObjects.map((item,index) => {
    return Object.entries(item).map(([key,value]) => {
        if(Array.isArray(value)){
            value.forEach(x => {
                newItemsArray.push({[key]:x})    
            })
            
        }
    })
})
iteration arrays loops javascript
2 Answers

You could check if the entries of the object contains an array and reduce the entries or take the object for mapping.

const
    data = [{ "Serial Number": "83675327350061093222581609820467", "Part Number": "LJ98-10C779-AA", "Cell Count": "32", "Length": "6" }, { "Serial Number": "19584757350061093222581606739916", "Type": "Extended Range", "Part Number": "SW23", "Length": "50" }, { "Serial Number": [ "90946117350061093222581604839920", "77362117350061093222581604891733", "77362117350061093222581604891734"], "Part Number": [ "TR40-60C779-AA", "ST41-60C780-AA", "ZT41-60C780-AA"], "Cell Count": [ "28", "27", "26"], "Length": [ "10", "11", "12"] }],
    result = data.flatMap(object => {
        const entries = Object.entries(object);
        return Array.isArray(entries[0][1])
            ? entries.reduce((r, [k, a]) => a.map((v, i) => ({ ...r[i], [k]: v })), [])
            : object;
    });

console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }

Without flatMap

const
    data = [{ "Serial Number": "83675327350061093222581609820467", "Part Number": "LJ98-10C779-AA", "Cell Count": "32", "Length": "6" }, { "Serial Number": "19584757350061093222581606739916", "Type": "Extended Range", "Part Number": "SW23", "Length": "50" }, { "Serial Number": [ "90946117350061093222581604839920", "77362117350061093222581604891733", "77362117350061093222581604891734"], "Part Number": [ "TR40-60C779-AA", "ST41-60C780-AA", "ZT41-60C780-AA"], "Cell Count": [ "28", "27", "26"], "Length": [ "10", "11", "12"] }],
    result = data.reduce((array, object) => {
        const entries = Object.entries(object);
        if (Array.isArray(entries[0][1])) return [
            ...array,
            entries.reduce((r, [k, a]) => a.map((v, i) => ({ ...r[i], [k]: v })), [])
        ];
        return [...array, object];
    }, []);

console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }

user_14476750

You can use Array#reduce and Object.keys with Array#map methods as follows:

const input = [
  {
      "Serial Number": "83675327350061093222581609820467",
      "Part Number": "LJ98-10C779-AA",
      "Cell Count": "32",
      "Length": "6"
  },
  {
      "Serial Number": "19584757350061093222581606739916",
      "Type": "Extended Range",
      "Part Number": "SW23",
      "Length": "50"
  },
  {
      "Serial Number": [
          "90946117350061093222581604839920",
          "77362117350061093222581604891733",
          "77362117350061093222581604891734",
      ],
      "Part Number": [
          "TR40-60C779-AA",
          "ST41-60C780-AA",
          "ZT41-60C780-AA",
      ],
      "Cell Count": [
          "28",
          "27",
          "26"
      ],
      "Length": [
          "10",
          "11",
          "12"
      ]
  }
];

const output = input.reduce((prev, {Length, ...rest}) => 
    Array.isArray(Length) ? 
    prev.concat( Length.map((l,i) => Object.fromEntries( Object.keys(rest).map(k => [k,rest[k][i]]).concat( [["Length",l]] ))) ) :
    prev.concat( {...rest,Length} ), []
);

console.log( output );

Without Object.fromEntries

const input = [
  {
      "Serial Number": "83675327350061093222581609820467",
      "Part Number": "LJ98-10C779-AA",
      "Cell Count": "32",
      "Length": "6"
  },
  {
      "Serial Number": "19584757350061093222581606739916",
      "Type": "Extended Range",
      "Part Number": "SW23",
      "Length": "50"
  },
  {
      "Serial Number": [
          "90946117350061093222581604839920",
          "77362117350061093222581604891733",
          "77362117350061093222581604891734",
      ],
      "Part Number": [
          "TR40-60C779-AA",
          "ST41-60C780-AA",
          "ZT41-60C780-AA",
      ],
      "Cell Count": [
          "28",
          "27",
          "26"
      ],
      "Length": [
          "10",
          "11",
          "12"
      ]
  }
];

const output = input.reduce((prev, {Length, ...rest}) => 
    Array.isArray(Length) ? 
    prev.concat( 
        Length.map((l,i) => 
        Object.keys(rest).map(k => ({[k]:rest[k][i]})).concat( {"Length":l} )
        .reduce((p,c) => ({...p,...c}),{}) ) 
    )  :
    prev.concat( {...rest,Length} ), []
);

console.log( output );

user_35589310
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