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Remove Object from Array using JavaScript

How can I remove an object from an array? I wish to remove the object that includes name Kristian from someArray. For example:

someArray = [{name:"Kristian", lines:"2,5,10"},
             {name:"John", lines:"1,19,26,96"}];

I want to achieve:

someArray = [{name:"John", lines:"1,19,26,96"}];

K
KooiInc

You can use several methods to remove item(s) from an Array:

//1
someArray.shift(); // first element removed
//2
someArray = someArray.slice(1); // first element removed
//3
someArray.splice(0, 1); // first element removed
//4
someArray.pop(); // last element removed
//5
someArray = someArray.slice(0, someArray.length - 1); // last element removed
//6
someArray.length = someArray.length - 1; // last element removed

If you want to remove element at position x, use:

someArray.splice(x, 1);

Or

someArray = someArray.slice(0, x).concat(someArray.slice(-x));

Reply to the comment of @chill182: you can remove one or more elements from an array using Array.filter, or Array.splice combined with Array.findIndex (see MDN), e.g.

// non destructive filter > noJohn = John removed, but someArray will not change let someArray = getArray(); let noJohn = someArray.filter( el => el.name !== "John" ); log(`let noJohn = someArray.filter( el => el.name !== "John")`, `non destructive filter [noJohn] =`, format(noJohn)); log(`**someArray.length ${someArray.length}`); // destructive filter/reassign John removed > someArray2 = let someArray2 = getArray(); someArray2 = someArray2.filter( el => el.name !== "John" ); log("", `someArray2 = someArray2.filter( el => el.name !== "John" )`, `destructive filter/reassign John removed [someArray2] =`, format(someArray2)); log(`**someArray2.length after filter ${someArray2.length}`); // destructive splice /w findIndex Brian remains > someArray3 = let someArray3 = getArray(); someArray3.splice(someArray3.findIndex(v => v.name === "Kristian"), 1); someArray3.splice(someArray3.findIndex(v => v.name === "John"), 1); log("", `someArray3.splice(someArray3.findIndex(v => v.name === "Kristian"), 1),`, `destructive splice /w findIndex Brian remains [someArray3] =`, format(someArray3)); log(`**someArray3.length after splice ${someArray3.length}`); // if you're not sure about the contents of your array, // you should check the results of findIndex first let someArray4 = getArray(); const indx = someArray4.findIndex(v => v.name === "Michael"); someArray4.splice(indx, indx >= 0 ? 1 : 0); log("", `someArray4.splice(indx, indx >= 0 ? 1 : 0)`, `check findIndex result first [someArray4] = (nothing is removed)`, format(someArray4)); log(`**someArray4.length (should still be 3) ${someArray4.length}`); // -- helpers -- function format(obj) { return JSON.stringify(obj, null, " "); } function log(...txt) { document.querySelector("pre").textContent += `${txt.join("\n")}\n` } function getArray() { return [ {name: "Kristian", lines: "2,5,10"}, {name: "John", lines: "1,19,26,96"}, {name: "Brian", lines: "3,9,62,36"} ]; }

**Results**


@Klemzy didnt you mean not by index ? by value ...?
The original question asked how to remove the object with the name="Kristian" from the array. Your answer assumes it's the first item in the array but what if Kristin is not in the first item? Then your answer doesn't work.
@chill182: it's not a specific answer, but a more general one. From it, you should be able to infer the method to remove elements. If you want to remove element at position x ... may be a hint for removing other than first elements, right?
The splice function was helpful to me, but you shouldn't have re-assigned someArray. This will result in someArray containing the removed item, instead of it containing the resulting array with the item removed.
You should check the findIndex result before using it in splice. If there are no elements in the array that match the condition findIndex will return -1and putting this directly into splice will result in an arbitraty deletion of the last element in the array.
S
Simon

The clean solution would be to use Array.filter:

var filtered = someArray.filter(function(el) { return el.Name != "Kristian"; }); 

The problem with this is that it does not work on IE < 9. However, you can include code from a Javascript library (e.g. underscore.js) that implements this for any browser.


This however will remove all the occurrences found, not only the first one
And it will return a new array instead of modifying the original one. Depending on the use case, this may or may not be what you want.
@JochieNabuurs it is indeed a new array. However, the object remains the same. You can still modify each object's value and it will reflect on the original array's object.
To the point about this returning a new array, just changing the solution to someArray = someArray.filter(function(el) { return el.Name != "Kristian"; }); addresses that, no?
It will work, doubtless. But if you are concerning about memory management it will create a new object anyway. I don't wanna me picky, this is gonna work for quite any case. But if for any reason you are dealing with a really large array, you should handle removing elements using the same object.
T
Timo Giese

I recommend using lodash.js or sugar.js for common tasks like this:

// lodash.js
someArray = _.reject(someArray, function(el) { return el.Name === "Kristian"; });

// sugar.js
someArray.remove(function(el) { return el.Name === "Kristian"; });

in most projects, having a set of helper methods that is provided by libraries like these is quite useful.


I think the underscore example is slightly off. Should be someArray = _.reject(someArray, function(el) { return el.Name === "Kristian"; });
If you don't want to use underscore.js or sugar.js, you can do this someArray = someArray.filter(function(e) { return e.Name !== "Kristian"; });
another thing i want, There will be separate buttons for every object in array. if i want to delete that particular object in the array button clicked. how to do it . i have used angular js ng-repeat to generate items. can you help me
Going to go against the grain here; suggesting one include an entire library for the simple purpose of removing items from objects (which js cleanly supports out of the box, as the accepted answer shows) is poor form. It adds unnecessary weight and complexity to your code unless you already need it for the more powerful functionality the library provides.
For simple operation , i will never recommend to include library
S
Saeid

ES2015

let someArray = [
               {name:"Kristian", lines:"2,5,10"},
               {name:"John", lines:"1,19,26,96"},
               {name:"Kristian", lines:"2,58,160"},
               {name:"Felix", lines:"1,19,26,96"}
            ];

someArray = someArray.filter(person => person.name != 'John');

It will remove John!


Man... Coming from java, I'm highgly confused that such a basic thing to do requires filtering of a list... wtf. This is the most accurate answer to OPs question I read so far.
Yes, this is a good approach. Though it will also work prior to ES2015(ES6). The filter function has been available since version 5.1(2011) ecma-international.org/ecma-262/5.1/#sec-15.4.4.20
Nice and clean :)
I use this one-line-solution with success in my case, it is very adaptive too : the condition can easily be customized.
A
Allan Taylor

How about this?

$.each(someArray, function(i){
    if(someArray[i].name === 'Kristian') {
        someArray.splice(i,1);
        return false;
    }
});

Won't that cause an error because $.each() caches the array length before looping so if you remove an element $.each() will run past the end of the (now shorter) array. (So then someArray[i] will be undefined and undefined.name will crash.)
Then add a 'return false' after the splice.
this is not javascript. -1
Please note that this answer requires jQuery
n
nnnnnn

Your "array" as shown is invalid JavaScript syntax. Curly brackets {} are for objects with property name/value pairs, but square brackets [] are for arrays - like so:

someArray = [{name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}];

In that case, you can use the .splice() method to remove an item. To remove the first item (index 0), say:

someArray.splice(0,1);

// someArray = [{name:"John", lines:"1,19,26,96"}];

If you don't know the index but want to search through the array to find the item with name "Kristian" to remove you could to this:

for (var i =0; i < someArray.length; i++)
   if (someArray[i].name === "Kristian") {
      someArray.splice(i,1);
      break;
   }

EDIT: I just noticed your question is tagged with "jQuery", so you could try the $.grep() method:

someArray = $.grep(someArray,
                   function(o,i) { return o.name === "Kristian"; },
                   true);

Why did they add the overload? Surely you could have just put != "Kristian". What purpose does the overload serve?
@markthewizard1234 - Do you mean the "invert" Boolean argument in $.grep()? It doesn't add much in this example, where yes, I could've put !=, but in other cases you might already have a function defined that happens to do the opposite test to what you want to grep, so then rather than defining an additional function you can just use that overload to invert the results.
Ah, so if you had a wrapper function containing the grep you could set the boolean as a parameter. Got it thanks!
@markthewizard1234 - You could, but that's not what I had in mind: imagine you had function isEven(num) { return num%2===0 }. You could use $.grep(someArray, isEven) to get just the even numbers from the array, or $.grep(someArray, isEven, true) to do the opposite and get the non-even values.
d
daCoda

You could use array.filter().

e.g.

        someArray = [{name:"Kristian", lines:"2,5,10"},
                     {name:"John", lines:"1,19,26,96"}];

        someArray = someArray.filter(function(returnableObjects){
               return returnableObjects.name !== 'Kristian';
        });

        //someArray will now be = [{name:"John", lines:"1,19,26,96"}];

Arrow functions:

someArray = someArray.filter(x => x.name !== 'Kristian')

another thing i want, There will be separate buttons for every object in array. if i want to delete that particular object in the array button clicked. how to do it . i have used angular js ng-repeat to generate items. can you help me
daCoda what if you have two conditions?
@MalcolmSalvador say for example if you have another conditions you can write this like below and continue with different && or || operator according to your need. someArray = someArray.filter(function(returnableObjects){ return returnableObjects.name !== 'Kristian' && cond2Query.age >= 22; });
B
Bishoy Hanna

I have made a dynamic function takes the objects Array, Key and value and returns the same array after removing the desired object:

function removeFunction (myObjects,prop,valu)
        {
             return myObjects.filter(function (val) {
              return val[prop] !== valu;
          });

        }

Full Example: DEMO

var obj = {
            "results": [
              {
                  "id": "460",
                  "name": "Widget 1",
                  "loc": "Shed"
              }, {
                  "id": "461",
                  "name": "Widget 2",
                  "loc": "Kitchen"
              }, {
                  "id": "462",
                  "name": "Widget 3",
                  "loc": "bath"
              }
            ]
            };


        function removeFunction (myObjects,prop,valu)
        {
             return myObjects.filter(function (val) {
              return val[prop] !== valu;
          });

        }


console.log(removeFunction(obj.results,"id","460"));

g
ggmendez

This is a function that works for me:

function removeFromArray(array, value) {
    var idx = array.indexOf(value);
    if (idx !== -1) {
        array.splice(idx, 1);
    }
    return array;
}

another thing i want, There will be separate buttons for every object in array. if i want to delete that particular object in the array button clicked. how to do it . i have used angular js ng-repeat to generate items. can you help me
A
Ammar

You could also try doing something like this:

var myArray = [{'name': 'test'}, {'name':'test2'}];
var myObject = {'name': 'test'};
myArray.splice(myArray.indexOf(myObject),1);

myArray.indexOf(myObject) returns -1, because no item was reference-equal to myObject. so splice() removes the -1th element in the array, which in this case is {'name':'test2'}!
A
Andre Morata
someArray = jQuery.grep(someArray , function (value) {
        return value.name != 'Kristian';
});

S
Sandeep Mukherjee
const someArray = [{name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}];

We get the index of the object which have name property value as "Kristian"

const index = someArray.findIndex(key => key.name === "Kristian");
console.log(index); // 0

By using splice function we are removing the object which have the name property value as "Kristian"

someArray.splice(index,1);
console.log(someArray); // [{name:"John", lines:"1,19,26,96"}]

One of the perfect answer. The rest above was such a waste of time.
@sg28 Thanks a lot ,i saw nobody explained it
g
gabitzish

Use splice function on arrays. Specify the position of the start element and the length of the subsequence you want to remove.

someArray.splice(pos, 1);

J
JuliaCesar

Vote for the UndercoreJS for simple work with arrays.

_.without() function helps to remove an element:

 _.without([1, 2, 1, 0, 3, 1, 4], 0, 1);
    => [2, 3, 4]

The best solution. Works with object arrays.
K
Kamil Kiełczewski

Performance

Today 2021.01.27 I perform tests on MacOs HighSierra 10.13.6 on Chrome v88, Safari v13.1.2 and Firefox v84 for chosen solutions.

Results

For all browsers:

fast/fastest solutions when element not exists: A and B

fast/fastest solutions for big arrays: C

fast/fastest solutions for big arrays when element exists: H

quite slow solutions for small arrays: F and G

quite slow solutions for big arrays: D, E and F

https://i.stack.imgur.com/woivl.png

Details

I perform 4 tests cases:

small array (10 elements) and element exists - you can run it HERE

small array (10 elements) and element NOT exists - you can run it HERE

big array (milion elements) and element exists - you can run it HERE

big array (milion elements) and element NOT exists - you can run it HERE

Below snippet presents differences between solutions A B C D E F G H I

function A(arr, name) { let idx = arr.findIndex(o => o.name==name); if(idx>=0) arr.splice(idx, 1); return arr; } function B(arr, name) { let idx = arr.findIndex(o => o.name==name); return idx<0 ? arr : arr.slice(0,idx).concat(arr.slice(idx+1,arr.length)); } function C(arr, name) { let idx = arr.findIndex(o => o.name==name); delete arr[idx]; return arr; } function D(arr, name) { return arr.filter(el => el.name != name); } function E(arr, name) { let result = []; arr.forEach(o => o.name==name || result.push(o)); return result; } function F(arr, name) { return _.reject(arr, el => el.name == name); } function G(arr, name) { let o = arr.find(o => o.name==name); return _.without(arr,o); } function H(arr, name) { $.each(arr, function(i){ if(arr[i].name === 'Kristian') { arr.splice(i,1); return false; } }); return arr; } function I(arr, name) { return $.grep(arr,o => o.name!=name); } // Test let test1 = [ {name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}, ]; let test2 = [ {name:"John3", lines:"1,19,26,96"}, {name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}, {name:"Joh2", lines:"1,19,26,96"}, ]; let test3 = [ {name:"John3", lines:"1,19,26,96"}, {name:"John", lines:"1,19,26,96"}, {name:"Joh2", lines:"1,19,26,96"}, ]; console.log(` Test1: original array from question Test2: array with more data Test3: array without element which we want to delete `); [A,B,C,D,E,F,G,H,I].forEach(f=> console.log(` Test1 ${f.name}: ${JSON.stringify(f([...test1],"Kristian"))} Test2 ${f.name}: ${JSON.stringify(f([...test2],"Kristian"))} Test3 ${f.name}: ${JSON.stringify(f([...test3],"Kristian"))} `)); This shippet only presents functions used in performance tests - it not perform tests itself!

And here are example results for chrome

https://i.stack.imgur.com/ZO8TD.png


J
Jafar Karuthedath

Here is an example with map and splice

const arrayObject = [ { name: "name1", value: "value1" }, { name: "name2", value: "value2" }, { name: "name3", value: "value3" }, ]; let index = arrayObject.map((item) => item.name).indexOf("name1"); if (index > -1) { arrayObject.splice(index, 1); console.log("Result", arrayObject); }

Output

Result [
  {
    "name": "name2",
    "value": "value2"
  },
  {
    "name": "name3",
    "value": "value3"
  }
]

This will also work in IE11, while answers with findIndex won't.
S
Siddhartha

With ES 6 arrow function

let someArray = [
                 {name:"Kristian", lines:"2,5,10"},
                 {name:"John", lines:"1,19,26,96"}
                ];
let arrayToRemove={name:"Kristian", lines:"2,5,10"};
someArray=someArray.filter((e)=>e.name !=arrayToRemove.name && e.lines!= arrayToRemove.lines)

d
dougajmcdonald

Although this is probably not that appropriate for this situation I found out the other day that you can also use the delete keyword to remove an item from an array if you don't need to alter the size of the array e.g.

var myArray = [1,2,3];

delete myArray[1];

console.log(myArray[1]); //undefined

console.log(myArray.length); //3 - doesn't actually shrink the array down

C
Creynders

Simplest solution would be to create a map that stores the indexes for each object by name, like this:

//adding to array
var newPerson = {name:"Kristian", lines:"2,5,10"}
someMap[ newPerson.name ] = someArray.length;
someArray.push( newPerson );

//deleting from the array
var index = someMap[ 'Kristian' ];
someArray.splice( index, 1 );

I like this idea, but must also ask, what are the memory use limits for an idea like this as indexes are added? I have an array that I'd like to index on 2 different fields in the object, so I'd have 2 maps in addition to the original source array. Is this a small price to pay for lookup speed or is there a solution that would be more efficient with memory?
s
solanki...

You can use map function also.

someArray = [{name:"Kristian", lines:"2,5,10"},{name:"John",lines:"1,19,26,96"}];
newArray=[];
someArray.map(function(obj, index){
    if(obj.name !== "Kristian"){
       newArray.push(obj);
    }
});
someArray = newArray;
console.log(someArray);

But if you want to iterate through the array, isn't it better to use forEach ?
map() does iterate through an array.
k
ksugiarto

If you want to remove all occurrences of a given object (based on some condition) then use the javascript splice method inside a for the loop.

Since removing an object would affect the array length, make sure to decrement the counter one step, so that length check remains intact.

var objArr=[{Name:"Alex", Age:62},
  {Name:"Robert", Age:18},
  {Name:"Prince", Age:28},
  {Name:"Cesar", Age:38},
  {Name:"Sam", Age:42},
  {Name:"David", Age:52}
];

for(var i = 0;i < objArr.length; i ++)
{
  if(objArr[i].Age > 20)
  {
    objArr.splice(i, 1);
    i--;  //re-adjust the counter.
  }
}

The above code snippet removes all objects with age greater than 20.


S
Shiv Kumar

This answer

for (var i =0; i < someArray.length; i++)
   if (someArray[i].name === "Kristian") {
      someArray.splice(i,1);
   }

is not working for multiple records fulfilling the condition. If you have two such consecutive records, only the first one is removed, and the other one skipped. You have to use:

for (var i = someArray.length - 1; i>= 0; i--)
   ...

instead .


S
Simon Scarfe

There seems to be an error in your array syntax so assuming you mean an array as opposed to an object, Array.splice is your friend here:

someArray = [{name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}];
someArray.splice(1,1)

A
Apolo Reader

Use javascript's splice() function.

This may help: http://www.w3schools.com/jsref/jsref_splice.asp


A
Artur Grigio

You could also use some:

someArray = [{name:"Kristian", lines:"2,5,10"},
             {name:"John", lines:"1,19,26,96"}];

someArray.some(item => { 
    if(item.name === "Kristian") // Case sensitive, will only remove first instance
        someArray.splice(someArray.indexOf(item),1) 
})

M
Matthias S

This is what I use.

Array.prototype.delete = function(pos){
    this[pos] = undefined;
    var len = this.length - 1;
    for(var a = pos;a < this.length - 1;a++){
      this[a] = this[a+1];
    }
    this.pop();
  }

Then it is as simple as saying

var myArray = [1,2,3,4,5,6,7,8,9];
myArray.delete(3);

Replace any number in place of three. After the expected output should be:

console.log(myArray); //Expected output 1,2,3,5,6,7,8,9

Your delete function is just a worse version of splice.
u
umutyerebakmaz

I guess the answers are very branched and knotted.

You can use the following path to remove an array object that matches the object given in the modern JavaScript jargon.


coordinates = [
    { lat: 36.779098444109145, lng: 34.57202827508546 },
    { lat: 36.778754712956506, lng: 34.56898128564454 },
    { lat: 36.777414146732426, lng: 34.57179224069215 }
];

coordinate = { lat: 36.779098444109145, lng: 34.57202827508546 };

removeCoordinate(coordinate: Coordinate): Coordinate {
    const found = this.coordinates.find((coordinate) => coordinate == coordinate);
    if (found) {
      this.coordinates.splice(found, 1);
    }
    return coordinate;
  }

M
Maksood

splice(i, 1) where i is the incremental index of the array will remove the object. But remember splice will also reset the array length so watch out for 'undefined'. Using your example, if you remove 'Kristian', then in the next execution within the loop, i will be 2 but someArray will be a length of 1, therefore if you try to remove "John" you will get an "undefined" error. One solution to this albeit not elegant is to have separate counter to keep track of index of the element to be removed.


L
Legends

Returns only objects from the array whose property name is not "Kristian"

var noKristianArray = $.grep(someArray, function (el) { return el.name!= "Kristian"; });

Demo:

var someArray = [ {name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}, {name:"Kristian", lines:"2,58,160"}, {name:"Felix", lines:"1,19,26,96"} ]; var noKristianArray = $.grep(someArray, function (el) { return el.name!= "Kristian"; }); console.log(noKristianArray);


S
Siva Ragu

This Concepts using Kendo Grid

var grid = $("#addNewAllergies").data("kendoGrid");

var selectedItem = SelectedCheckBoxList;

for (var i = 0; i < selectedItem.length; i++) {
    if(selectedItem[i].boolKendoValue==true)
    {
        selectedItem.length= 0;
    }
}