Jquery check if array contains duplicate string

Question

How to check if array contains a duplicate string , i have validateArray = [\'sa\',\'sa\',\'yu\'] i have used the following function from SO but same not working for me.

Answer 1

This is working for me:

var reportRecipients = ['AAA', 'XYZ', 'AAA', 'ABC', 'XXX', 'XYZ', 'PQR'];
var recipientsArray = reportRecipients.sort(); 

var reportRecipientsDuplicate = [];
for (var i = 0; i < recipientsArray.length - 1; i++) {
    if (recipientsArray[i + 1] == recipientsArray[i]) {
        reportRecipientsDuplicate.push(recipientsArray[i]);
    }
}

Hope that helps.