var contacts = [
    { account: "Acme", firstName: "John", lastName: "Snow" },
    { account: "Metal Industries", firstName: "Ted", lastName: "Smith" },
    { account: "Acme", firstName: "Sara", lastName: "Butler" },
    { account: "HiTech Corp", firstName: "Sam", lastName: "Johnson" },
    { account: "HiTech Corp", firstName: "Arnold", lastName: "Williams" },
    { account: "Metal Industries", firstName: "Jessica", lastName: "Westcoat" },
    { account: "Acme", firstName: "Kyle", lastName: "Johnson" },
    { account: "HiTech Corp", firstName: "Jason", lastName: "Fernandez" }
  ];

The goal is to get this output:

  result =  {
    "Acme": ["John Snow", "Kyle Johnson", "Sara Butler"],
    "HiTech Corp": ["Arnold Williams", "Jason Fernandez", "Sam Johnson"],
    "Metal Industries": ["Jessica Westcoat", "Ted Smith"]
  }

My function below is not returning the array of values and only returns the last value

  const convertArrayToObject = (array, key) => {
    const initialValue = {}
    return array.reduce((obj, item) => {
        return {...obj,[item[key]]: item,}
    }, initialValue)
  }

Output

Any help is appreciated

CodePudding user response：

You were close, just missing that when you set up the object in the resultant array, you need to set it as an array - in this script that would be [k]: [v] and not [k]: v

var contacts = [
    { account: "Acme", firstName: "John", lastName: "Snow" },
    { account: "Metal Industries", firstName: "Ted", lastName: "Smith" },
    { account: "Acme", firstName: "Sara", lastName: "Butler" },
    { account: "HiTech Corp", firstName: "Sam", lastName: "Johnson" },
    { account: "HiTech Corp", firstName: "Arnold", lastName: "Williams" },
    { account: "Metal Industries", firstName: "Jessica", lastName: "Westcoat" },
    { account: "Acme", firstName: "Kyle", lastName: "Johnson" },
    { account: "HiTech Corp", firstName: "Jason", lastName: "Fernandez" }
  ];


const convertArrayToObject = (array, key) => {
  const initialValue = {}
  return array.reduce((obj, item) => {
    let k = item[key], v=item.firstName   ' '   item.lastName;
    if (obj[k]) obj[k].push(v);
    else obj = { ...obj, [k]: [v] }
    return obj
  }, initialValue)
}

console.log(convertArrayToObject(contacts, 'account'))

<iframe name="sif1" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

CodePudding user response：

const convertArrayToObject = (array, key) => {
    const initialValue = {}
    array.forEach((obj, item) => {
        initialValue[obj.account] = initialValue[obj.account] || []
        initialValue[obj.account].push(`${obj.firstName} ${obj.lastName}`)
    })
    return initialValue
}