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"}];

Solution 1:

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"} ];
}

<pre>
**Results**

</pre>

Solution 2:

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.

Solution 3:

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.

Solution 4:

How about this?

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

Solution 5:

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!