Remove specified JSON elements according to a designated list of permitted elements

Question

Remove specified JSON elements according to a designated list of permitted elements

My task involves filtering an array of allowedFields that corresponds to the keys in a JSON array created from a form.

Some fields obtained are not necessary for validation at this point, so I aim to compare the values in the JSON array with those in the allowedFields array.

JSON data received from form:

{"reference":"sdfsdfsdfsd",
"start_date":"04/22/2014",
"end_date":"05//2014",
"status":"1","frequency":"M",
"day":"sat",
"contract_type":"S",
"notice_period":"1M"}

allowedFields = array(
     reference,
     start_date,
     end_date,
     contract_type
)

In essence, my goal is to remove any fields that are not included in the allowedFields JavaScript array.

javascript arrays json

Answer 1

Answer №1

Step 1: Convert the JSON data into an object.

let data = '"name":"John Doe","age":30,"city":"New York"';
let obj = JSON.parse(data);

Step 2: Define the array with allowed fields.

let fieldsArray = ['name', 'age', 'city'];

Step 3: Iterate over the object and remove any keys that are not in the defined array.

for (let key in obj) {
   if (!fieldsArray.includes(key)) {
       delete obj[key];
   }
}

Step 4: Convert the filtered object back to JSON format.

let filteredData = JSON.stringify(obj);

Final Output:

{"name": "John Doe", "age": 30, "city": "New York"}

Example link

Answer 2

Step 1: Convert the JSON data into an object.

let data = '"name":"John Doe","age":30,"city":"New York"';
let obj = JSON.parse(data);

Step 2: Define the array with allowed fields.

let fieldsArray = ['name', 'age', 'city'];

Step 3: Iterate over the object and remove any keys that are not in the defined array.

for (let key in obj) {
   if (!fieldsArray.includes(key)) {
       delete obj[key];
   }
}

Step 4: Convert the filtered object back to JSON format.

let filteredData = JSON.stringify(obj);

Final Output:

{"name": "John Doe", "age": 30, "city": "New York"}

Example link

Answer 3

Answer №2

let data = {"name":"John Doe",
            "age":30};
let allowedProps = ['name']; // storing properties in an array

function filterData(obj, props) {
   let filteredObj = {};
   for(let prop of props) {
      if(obj.hasOwnProperty(prop)) {
         filteredObj[prop] = obj[prop];
      }
   }
   return filteredObj;
}

console.log(filterData(data, allowedProps));
>> [object Object] {
>>  name: "John Doe"
>> }

Demo

Answer 4

let data = {"name":"John Doe",
            "age":30};
let allowedProps = ['name']; // storing properties in an array

function filterData(obj, props) {
   let filteredObj = {};
   for(let prop of props) {
      if(obj.hasOwnProperty(prop)) {
         filteredObj[prop] = obj[prop];
      }
   }
   return filteredObj;
}

console.log(filterData(data, allowedProps));
>> [object Object] {
>>  name: "John Doe"
>> }

Demo

Answer 5

Answer №3

underscore.js solution:

_.selectFields(obj,allowedKeys)

http://underscorejs.org/#selectFields

demo

Another option is to use _.exclude(obj,string|string[]) for the opposite effect.

Working with underscore.js can significantly improve your code efficiency. While the library offers a range of functionalities, you can also choose specific tools that best suit your needs. This way, you can optimize performance without needing to reinvent the wheel.

Check out the sample implementation below (source: here)

_.selectFields = function(obj, filter, context) {
    var result = {};
    if (_.isFunction(filter)) {
      for (var key in obj) {
        var field = obj[key];
        if (filter.call(context, field, key, obj)) result[key] = field;
      }
    } else {
      var keys = concat.apply([], slice.call(arguments, 1));
      for (var i = 0, len = keys.length; i < len; i++) {
        var key = keys[i];
        if (key in obj) result[key] = obj[key];
      }
    }
    return result;
  };

Answer 6

underscore.js solution:

_.selectFields(obj,allowedKeys)

http://underscorejs.org/#selectFields

demo

Another option is to use _.exclude(obj,string|string[]) for the opposite effect.

Working with underscore.js can significantly improve your code efficiency. While the library offers a range of functionalities, you can also choose specific tools that best suit your needs. This way, you can optimize performance without needing to reinvent the wheel.

Check out the sample implementation below (source: here)

_.selectFields = function(obj, filter, context) {
    var result = {};
    if (_.isFunction(filter)) {
      for (var key in obj) {
        var field = obj[key];
        if (filter.call(context, field, key, obj)) result[key] = field;
      }
    } else {
      var keys = concat.apply([], slice.call(arguments, 1));
      for (var i = 0, len = keys.length; i < len; i++) {
        var key = keys[i];
        if (key in obj) result[key] = obj[key];
      }
    }
    return result;
  };

Remove specified JSON elements according to a designated list of permitted elements

Answer №1

Answer №2

Answer №3

Similar questions

Vue.js error: Unable to locate requested resources

Tips for removing unnecessary debugging code from JavaScript when compiling or minifying your code

Struggling to establish the default selection value in AngularJS

Vue 2 - Error: The function is not defined at HTMLInputElement.invoker (vue.esm.js?65d7:1810)TypeError: cloned[i].apply

Using Jquery to add text at the beginning of a Gmail signature

Adding information to a MySQL database using a variable - What's the best way?

The operation of "grunt build" results in a Lexer Error, causing the ng-include

The current version of 'buffer' is outdated. To resolve this issue, please upgrade to v4.9.2 or higher

What steps should be taken to link a frontend program on a separate port to a backend system?

Click on the image to resize the div accordingly

Unleashing the power of promises through chaining resolution and rejection

Are there specific files or classes that store constants for different keyboard events?

originalRenderPage has not been declared

Ensure the Json object contains an integer

Executing VueJS keyup handler after the previous onclick handler has been executed

Angular 4: Transform a string into an array containing multiple objects

Changing states in next.js is not accomplished by using setState

Tips on selecting a nested array in PHP

How can login errors be displayed in a Django application?

Getting started with TinyMCE in Nuxt: A step-by-step guide