public string SaveRegisterStuden(RegisterStudentModel registerStudentModel) { Registernumber(registerStudentModel); if (_registerStudentGateway.IsExistEmail(registerStudentModel) == null) { if (_registerStudentGateway.InsertRegisterStudent(registerStudentModel) > 0) { return("Save Successfull"); } else { return("Save Fail"); } } else { return(_registerStudentGateway.IsExistEmail(registerStudentModel)); } }