JavaScript array lastIndexOf() method

　JavaScript Array Object

lastIndexOf()The method returns the first character index value of a character or string from right to left (from the position where the string appears last), and returns if there is no match-1(opposite of indexOf).

If the element is not found, it will return-1.

If the element exists multiple times, it will return the position of the last occurrence.

If you want to search from the beginning to the end, useindexOf()Method.

Note:For more information on the String method, seeString.lastIndexOf().

Syntax:

array.lastIndexOf(element, start)

var fruits = ['Banana', 'Mango', 'Apple', 'Orange', 'Apple'];
fruits.lastIndexOf('Apple');//　returns　4

Browser compatibility

The numbers in the table specify the first browser version that fully supports the lastIndexOf() method:

Parameter value

Technical details

More Examples

Return the last position of the element 'Orange' in the position5Start searching (search backward):

　var fruits = ['Banana', 'Mango', 'Apple', 'Orange', 'Guava', 'Apple', 'Orange'];
fruits.lastIndexOf('Orange',　5);

If the given parameter is a value that does not exist in the array, it will return-1:

var fruits = ['Banana', 'Mango', 'Apple', 'Orange', 'Apple'];
fruits.lastIndexOf('Beer');//　returns　-1

If the element exists multiple times, it will return the position of the last occurrence:

var nums = [1,　4,　2,　3,　4,　5,　5,　4,　5]);
nums.lastIndexOf(4);

　JavaScript Array Object