how to get last index in array javascript

JavaScript
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
if (loc_array[loc_array.length - 1] === 'index.html') {
   // do something
} else {
   // something else
}console.log(2)
Source

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