Iterate over the object to verify if the field contains an empty array, then output null

Question

Iterate over the object to verify if the field contains an empty array, then output null

Looking for help with handling empty arrays in an object:

productDetails: {
    cislife: [],
    prime: []
  }

Is there a way to have null returned instead of an empty array if no values are available?

For example, I'd like to determine if either the 'cislife' or 'prime' array is empty and return null as the value. If 'prime' has values but 'cislife' does not, then I want to return the values for 'prime' and null for 'cislife'.

Any suggestions on how to tackle this issue?

javascript ecmascript-6

Answer 1

Answer №1

You have the option to utilize Array.prototype.reduce in order to construct an object literal by replacing [] with null when necessary:

const productDetails = {
  cislife: [],
  prime: [],
  nonEmptyExample: [1, 2, 3],
  nonArrayExample: 'a string!'
};

const emptyArraysToNulls = o => {
  return Object.entries(productDetails).reduce((accum, entry) => {
    const [key, val] = entry;
    if (Array.isArray(val)) {
      accum[key] = val.length === 0 ? null : val;
    } else {
      accum[key] = val;
    }

    return accum;
  }, {});
};

console.log(emptyArraysToNulls(productDetails));

Answer 2

You have the option to utilize Array.prototype.reduce in order to construct an object literal by replacing [] with null when necessary:

const productDetails = {
  cislife: [],
  prime: [],
  nonEmptyExample: [1, 2, 3],
  nonArrayExample: 'a string!'
};

const emptyArraysToNulls = o => {
  return Object.entries(productDetails).reduce((accum, entry) => {
    const [key, val] = entry;
    if (Array.isArray(val)) {
      accum[key] = val.length === 0 ? null : val;
    } else {
      accum[key] = val;
    }

    return accum;
  }, {});
};

console.log(emptyArraysToNulls(productDetails));

Answer 3

Answer №2

A clever method to generate the desired array without altering the original one is shown below:

const initialObject = {
  cislife: [],
  prime: [],
  nonArrayField: "I'm not an array, keep me as it is!"
};

const resultObject = {
  ...initialObject,
  ...Object.keys(initialObject)
    // remove keys that do not belong to empty arrays
    .filter(key => Array.isArray(initialObject[key]) && !initialObject[key].length)
    // replace empty arrays with null values
    .reduce((acc, key) => ({ ...acc, [key]: null }), {}),
};

console.log(resultObject);

Answer 4

A clever method to generate the desired array without altering the original one is shown below:

const initialObject = {
  cislife: [],
  prime: [],
  nonArrayField: "I'm not an array, keep me as it is!"
};

const resultObject = {
  ...initialObject,
  ...Object.keys(initialObject)
    // remove keys that do not belong to empty arrays
    .filter(key => Array.isArray(initialObject[key]) && !initialObject[key].length)
    // replace empty arrays with null values
    .reduce((acc, key) => ({ ...acc, [key]: null }), {}),
};

console.log(resultObject);

Answer 5

Answer №3

One way to enhance your object editing skills is by utilizing getters

var productDetails = {
  _cislife: [],
  get cislife() {
    return this._cislife.length ? this._cislife : null
  },
  _prime: [],
  get prime() {
    return this.prime.length ? this.prime : null
  },
}

console.log(productDetails.cislife)

Answer 6

One way to enhance your object editing skills is by utilizing getters

var productDetails = {
  _cislife: [],
  get cislife() {
    return this._cislife.length ? this._cislife : null
  },
  _prime: [],
  get prime() {
    return this.prime.length ? this.prime : null
  },
}

console.log(productDetails.cislife)

Answer 7

Answer №4

To access the data, utilize getter functions as shown below:

let customerData = {
    _loyaltyPoints: 150,
    _purchaseHistory: [],

    get loyaltyPoints() {
        return this._loyaltyPoints;
    },

    get purchaseHistory() {
        return this._purchaseHistory.length == 0 ? "No purchases made yet" : this._purchaseHistory;
    }
}

console.log(customerData.loyaltyPoints); // 150
console.log(customerData.purchaseHistory); // No purchases made yet

Answer 8

To access the data, utilize getter functions as shown below:

let customerData = {
    _loyaltyPoints: 150,
    _purchaseHistory: [],

    get loyaltyPoints() {
        return this._loyaltyPoints;
    },

    get purchaseHistory() {
        return this._purchaseHistory.length == 0 ? "No purchases made yet" : this._purchaseHistory;
    }
}

console.log(customerData.loyaltyPoints); // 150
console.log(customerData.purchaseHistory); // No purchases made yet

Iterate over the object to verify if the field contains an empty array, then output null

Answer №1

Answer №2

Answer №3

Answer №4

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