Javascript String endsWith(searchString, position)

 String.prototype.endsWith = function (searchString, position) {
    var subjectString = this.toString();
    if (typeof position !== 'number' || !isFinite(position) || Math.floor(position) !== position || position > subjectString.length) {
        position = subjectString.length;
    }/*from  w ww .  j  av  a  2s . c om*/
    position -= searchString.length;
    var lastIndex = subjectString.lastIndexOf(searchString, position);
    return lastIndex !== -1 && lastIndex === position;
};