// if enter key pressed after pasting/typing PNR status Ajax method will be called
$(‘#PNR_NUM’).on(‘keypress’, function (event) {
if(event.which === 13){
loadPNRStatus();
}
// return false if user enters other than numbers
if (event.which != 8 && event.which != 0 && (event.which < 48 || event.which > 57)) {
//display error message
return false;
}
});