Update:
You could remove a property from an object with a tricky Destructuring assignment:
const doSomething = (obj, prop) => {
let {[prop]: omit, ...res} = obj
return res
}
Though, if property name you want to remove is static, then you could remove it with a simple one-liner:
let {lastname, ...o2} = o
The easiest way is simply to Or you could clone your object before mutating it:
const doSomething = (obj, prop) => {
let res = Object.assign({}, obj)
delete res[prop]
return res
}
Alternatively you could use omit function from lodash utility library:
let o2 = _.omit(o, 'lastname')
It's available as a part of lodash package, or as a standalone lodash.omit package.
Answer from Leonid Beschastny on Stack Overflow
Update:
You could remove a property from an object with a tricky Destructuring assignment:
const doSomething = (obj, prop) => {
let {[prop]: omit, ...res} = obj
return res
}
Though, if property name you want to remove is static, then you could remove it with a simple one-liner:
let {lastname, ...o2} = o
The easiest way is simply to Or you could clone your object before mutating it:
const doSomething = (obj, prop) => {
let res = Object.assign({}, obj)
delete res[prop]
return res
}
Alternatively you could use omit function from lodash utility library:
let o2 = _.omit(o, 'lastname')
It's available as a part of lodash package, or as a standalone lodash.omit package.
With ES7 object destructuring:
const myObject = {
a: 1,
b: 2,
c: 3
};
const { a, ...noA } = myObject;
console.log(noA); // => { b: 2, c: 3 }
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 unchangedObjects 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')) // falseThe 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.
The delete operator allows you to remove a property from an object.
The following examples all do the same thing.
// Example 1
var key = "Cow";
delete thisIsObject[key];
// Example 2
delete thisIsObject["Cow"];
// Example 3
delete thisIsObject.Cow;
let animals = {
'Cow': 'Moo',
'Cat': 'Meow',
'Dog': 'Bark'
};
delete animals.Cow;
delete animals['Dog'];
console.log(animals);If you're interested, read Understanding Delete for an in-depth explanation.
If you are using Underscore.js or Lodash, there is a function 'omit' that will do it.
http://underscorejs.org/#omit
var thisIsObject= {
'Cow' : 'Moo',
'Cat' : 'Meow',
'Dog' : 'Bark'
};
_.omit(thisIsObject,'Cow'); //It will return a new object
=> {'Cat' : 'Meow', 'Dog' : 'Bark'} //result
If you want to modify the current object, assign the returning object to the current object.
thisIsObject = _.omit(thisIsObject,'Cow');
With pure JavaScript, use:
delete thisIsObject['Cow'];
Another option with pure JavaScript.
thisIsObject = Object.keys(thisIsObject).filter(key =>
key !== 'cow').reduce((obj, key) =>
{
obj[key] = thisIsObject[key];
return obj;
}, {}
);