Model validation (mode Validation)

1. Clear Validation ModelValidated directly in the action in controller, eg:
[HttpPost]
Public Viewresult makebooking (Appointment appt) {

if (string. IsNullOrEmpty (appt. ClientName)) {
Modelstate.addmodelerror ("ClientName", "Please enter your name");
}

if (Modelstate.isvalidfield ("Date") && datetime.now > Appt. Date) {
Modelstate.addmodelerror ("date", "Please enter a date in the future");
}

if (!appt. termsaccepted) {
Modelstate.addmodelerror ("termsaccepted", "you must accept the terms");
}

if (modelstate.isvalid) {
Repository. Saveappointment (appt);
Return View ("Completed", appt);
} else {
return View ();
}
}
If validation does not pass, an error is done. The style of the error is defined in the input-validation-error of the ~/content/site.css file, which defaults to the following:
. input-validation-error {
border:1px solid #ff0000;
Background-color: #ffeeee;
}

The above wording just does not pass the verification, but does not give the error message, if wants to display the error message, must add in the view: @Html. ValidationSummary ()