lastIndex of javascript code example

Example 1: Javascript get last item in array

var colors = ["red","blue","green"];
var green = colors[colors.length - 1]; //get last item in the array

Example 2: js last index of

const str = "Users/Edit/12345";
let idx = str.lastIndexOf("/"); // returns 10
idx = str.lastIndexOf("x"); // returns -1

idx = str.lastIndexOf("Edit") // returns 6
idx = str.lastIndexOf("edit") // returns -1 -- case sensitive

// add "from" parameter
// the search happens backwards, starting at the provided from parameter
idx = str.lastIndexOf("s"); // returns 4
idx = str.lastIndexOf("s", 3); // returns 1

Example 3: lastindexof() javascript

'canal'.lastIndexOf('a');     // retorna 3
'canal'.lastIndexOf('a', 2);  // retorna 1
'canal'.lastIndexOf('a', 0);  // retorna -1
'canal'.lastIndexOf('x');     // retorna -1
'canal'.lastIndexOf('c', -5); // retorna 0
'canal'.lastIndexOf('c', 0);  // retorna 0
'canal'.lastIndexOf('');      // retorna 5
'canal'.lastIndexOf('', 2);   // retorna 2

Example 4: lastindexof js

string.lastIndexOf("subString")