javascript splice array code example

Example 1: remove element from array javascript

let fruit = ['apple', 'banana', 'orange', 'lettuce']; 
// ^^ An example array that needs to have one item removed

fruit.splice(3, 1); // Removes an item in the array using splice() method
// First argument is the index of removal
// Second argument is the amount of items to remove from that index and on

Example 2: javascript splice

let arr = ['foo', 'bar', 10, 'qux'];

// arr.splice(<index>, <steps>, [elements ...]);

arr.splice(1, 1);			// Removes 1 item at index 1
// => ['foo', 10, 'qux']

arr.splice(2, 1, 'tmp');	// Replaces 1 item at index 2 with 'tmp'
// => ['foo', 10, 'tmp']

arr.splice(0, 1, 'x', 'y');	// Inserts 'x' and 'y' replacing 1 item at index 0
// => ['x', 'y', 10, 'tmp']

Example 3: splice javascritp

let colors = ['red', 'blue', 'green'];

let index_element_to_be_delete = colors.indexOf('green');

colors.splice(index_element_to_be_delete); 

//Colors now: ['red', 'blue']

Example 4: prepend to array javascript

// Build an array of test data.
var data = [ "X" ];

// Unshift data onto the array. Unshift() prepends elements to
// the beginning of the given array. Note that it can take more
// than one argument. In the output, notice that when unshift()
// takes multiple arguments, they are prepended in a right-to-left
// order (mimicing their appearence in the arguments list).
data.unshift( "A" );
data.unshift( "B", "C" );

// Output resultant array.
console.log( data );

Example 5: splice javascript

const months = ['Jan', 'March', 'April', 'June'];
months.splice(1, 0, 'Feb');
// inserts at index 1
console.log(months);
// expected output: Array ["Jan", "Feb", "March", "April", "June"]

months.splice(4, 1, 'May');
// replaces 1 element at index 4
console.log(months);
// expected output: Array ["Jan", "Feb", "March", "April", "May"]

months.splice(0, 1);
// removes 1 element at index 0
console.log(months);
// expected output: Array ["Feb", "March", "April", "May"]

Example 6: splice javascript

const numbers = [10, 11, 12, 12, 15];
const startIndex = 3;
const amountToDelete = 1;

numbers.splice(startIndex, amountToDelete, 13, 14);
// the second entry of 12 is removed, and we add 13 and 14 at the same index
console.log(numbers);
// returns [ 10, 11, 12, 13, 14, 15 ]