remove element from object javascript

How do I remove a property from a JavaScript object?

stackoverflow.com › questions › 208105 › how-do-i-remove-a-property-from-a-javascript-object

To remove a property from an object (mutating the object), you can do it by using the delete keyword, like this:

delete myObject.regex;
// or,
delete myObject['regex'];
// or,
var prop = "regex";
delete myObject[prop];

Demo

var myObject = {
  "ircEvent": "PRIVMSG",
  "method": "newURI",
  "regex": "^http://.*"
};
delete myObject.regex;

console.log(myObject);

For anyone interested in reading more about it, Stack Overflow user kangax has written an incredibly in-depth blog post about the delete statement on their blog, Understanding delete. It is highly recommended.

If you'd like a new object with all the keys of the original except some, you could use destructuring.

Demo

let myObject = {
  "ircEvent": "PRIVMSG",
  "method": "newURI",
  "regex": "^http://.*"
};

// assign the key regex to the variable _ indicating it will be unused
const { regex: _, ...newObj } = myObject;

console.log(newObj);   // has no 'regex' key
console.log(myObject); // remains unchanged

Answer from nickf on Stack Overflow

MDN Web Docs

developer.mozilla.org › en-US › docs › Web › JavaScript › Reference › Operators › delete

delete - JavaScript - MDN Web Docs - Mozilla

The delete operator removes a property from an object. If the property's value is an object and there are no more references to the object, the object held by that property is eventually released automatically.

Stack Overflow

stackoverflow.com › questions › 208105 › how-do-i-remove-a-property-from-a-javascript-object

How do I remove a property from a JavaScript object? - Stack Overflow

Top answer

1 of 16

10001

To remove a property from an object (mutating the object), you can do it by using the delete keyword, like this:

delete myObject.regex;
// or,
delete myObject['regex'];
// or,
var prop = "regex";
delete myObject[prop];

Demo

var myObject = {
  "ircEvent": "PRIVMSG",
  "method": "newURI",
  "regex": "^http://.*"
};
delete myObject.regex;

console.log(myObject);

If you'd like a new object with all the keys of the original except some, you could use destructuring.

Demo

let myObject = {
  "ircEvent": "PRIVMSG",
  "method": "newURI",
  "regex": "^http://.*"
};

// assign the key regex to the variable _ indicating it will be unused
const { regex: _, ...newObj } = myObject;

console.log(newObj);   // has no 'regex' key
console.log(myObject); // remains unchanged

2 of 16

1130

Objects in JavaScript can be thought of as maps between keys and values. The delete operator is used to remove these keys, more commonly known as object properties, one at a time.

var obj = {
  myProperty: 1    
}
console.log(obj.hasOwnProperty('myProperty')) // true
delete obj.myProperty
console.log(obj.hasOwnProperty('myProperty')) // false

The delete operator does not directly free memory, and it differs from simply assigning the value of null or undefined to a property, in that the property itself is removed from the object. Note that if the value of a deleted property was a reference type (an object), and another part of your program still holds a reference to that object, then that object will, of course, not be garbage collected until all references to it have disappeared.

delete will only work on properties whose descriptor marks them as configurable.

How do I remove a property from a JavaScript object?

pointers - Deleting Objects in JavaScript

javascript - Delete a property from an object without creating a new one (No delete operateur)

removing elements from objects - javascript

javascript - Implement the removeProperty function that takes an object and a property name

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Best way to remove a nested object property without mutation?

In order to create a copy that is not just references to the original data, you need to make a deep copy rather than a shallow copy. You can do that like this: const myObj = { top1: 'some value', top2: { nested1: 'some value', nested2: 'remove this' } }; console.log(myObj); let myObjCopy = JSON.parse(JSON.stringify(myObj)); delete myObjCopy.top2.nested2; console.log(myObjCopy); The JSON.parse... creates a deep copy, then you just need to delete the desired nested property with the "delete" keyword. And you can see in each of the console.logs that each object is different from one another. oh yeah... and happy cake Day! More on reddit.com

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