validate.js

$(document).on('keyup', '.numeric', function(e){

        var val = false;
        var sKeys = [0, 8, 9, 16, 17, 18, 37, 38, 39, 40, 144];
        var re = /^[0-9]*$/; 
        var text = String.fromCharCode(e.keyCode);
        
        if(this.value){
            val = this.value;
        }else if(this.innerHTML){
            val = this.innerHTML;
        }

        if(!re.test(text) && val !== '' && sKeys.indexOf(e.keyCode) < 0 || (val !== false && !re.test(val))){
            $(this).addClass('input-error');
            return false;
        }

        $(this).removeClass('input-error');

    });