prevent excerpt typing after 115 characters

prevent-excerpt.js

jQuery(document).ready(function($) {
    var max = 115;
    $('#excerpt').keydown(function(e) {
        if(e.which == 8) {
            return;
        }
        if (e.target.value.length == max) {
            e.preventDefault();
        } else if (e.target.value.length > max) {
            // Maximum exceeded
            e.target.value = this.value.substring(0, max);
        }
    });
});