javascript – to remove first and last element in array-ThrowExceptions

Exception or error:

How to remove first and last element in an array?

For example:

var fruits = ["Banana", "Orange", "Apple", "Mango"];

Expected output array:

["Orange", "Apple"]
How to solve:
fruits.shift();  // Removes the first element from an array and returns only that element.
fruits.pop();    // Removes the last element from an array and returns only that element. 

See all methods for an Array.

###

Creates a 1 level deep copy.

fruits.slice(1, -1)

Let go of the original array.

Thanks to @Tim for pointing out the spelling errata.

###

var fruits = ["Banana", "Orange", "Apple", "Mango"];
var newFruits = fruits.slice(1, -1);
console.log(newFruits); //  ["Orange", "Apple"];

Here, -1 denotes the last element in an array and 1 denotes the second element.

###

I use splice method.

fruits.splice(0, 1); // Removes first array element

var lastElementIndex = fruits.length-1; // Gets last element index

fruits.splice(lastElementIndex, 1); // Removes last array element

To remove last element also you can do it this way:

fruits.splice(-1, 1);

See Remove last item from array to see more comments about it.

###

push() adds a new element to the end of an array.
pop() removes an element from the end of an array.

unshift() adds a new element to the beginning of an array.
shift() removes an element from the beginning of an array.

To remove first element from an array arr , use arr.shift()
To remove last element from an array arr , use arr.pop()

###

You can use Array.prototype.reduce().

Code:

const fruits = ['Banana', 'Orange', 'Apple', 'Mango'],
      result = fruits.reduce((a, c, i, array) => 0 === i || array.length - 1 === i ? a : [...a, c], []);

console.log(result);

###

To remove element from array is easy just do the following

let array_splited = [].split('/');
array_splited.pop()
array_splited.join('/')

###

This can be done with lodash _.tail and _.dropRight:

var fruits = ["Banana", "Orange", "Apple", "Mango"];
console.log(_.dropRight(_.tail(fruits)));
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script>

###

var resident_array =  ["RC_FRONT", "RC_BACK", "RC_BACK"];
var remove_item = "RC_FRONT";
resident_array = $.grep(resident_array, function(value) {
            return value != remove_item;
    });
resident_array = ["RC_BACK", "RC_BACK"];

###

Say you have array named list. The Splice() function can be used for both adding and removing item in that array in specific index i.e that can be in the beginning or in the end or at any index. On the contrary there are another function name shift() and pop() which is capable of removing only the first and last item in the array.

This is the Shift Function which is only capable of removing the first element of the array

var item = [ 1,1,2,3,5,8,13,21,34 ]; // say you have this number series 
item.shift(); // [ 1,2,3,5,8,13,21,34 ];

The Pop Function removes item from an array at its last index

item.pop(); // [ 1,2,3,5,8,13,21 ];

Now comes the splice function by which you can remove item at any index

item.slice(0,1); // [ 2,3,5,8,13,21 ] removes the first object
item.slice(item.length-1,1); // [ 2,3,5,8,13 ] removes the last object 

The slice function accepts two parameters (Index to start with, number of steps to go);

###

You used
Fruits.shift() method to first element remove .
Fruits.pop() method used for last element remove one by one if you used button click.
Fruits.slice( start position, delete element)You also used slice method for remove element in middle start.

###

To remove the first and last element of an array is by using the built-in method of an array i.e shift() and pop() the fruits.shift() get the first element of the array as “Banana” while fruits.pop() get the last element of the array as “Mango”. so the remaining element of the array will be ["Orange", "Apple"]

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