C# XMLSerialization error, System.InvalidOperationException

Question

i'm new to XMLSerialization, and have nobody near to help me out with it, so here is a part of code i want to XMLSerialize/Deserialize, and an error itself.

I have a three classes:

public class Contacts
{
    public string country;
    public string city;
    public string street;
    public int houseNumber;
    public int flatNumber;
    public int phoneNumber;

    public Contacts(){...};

    public Contacts(string cntry, string city, string str, int houseNum, int flatNum, int phoneNum){...};
    public override string ToString(){...};
}

public class SimpleHuman
{
    public string firstName;
    public string lastName;
    public int age;
    public string sex;
    public Contacts contacts;

    public SimpleHuman(){...};

    public SimpleHuman(string fn, string ln, int a, string s, Contacts c){...};

    public override string ToString(){...};
}

public class doctor : SimpleHuman
{
    public DateTime contractExpirationDate;
    public int idNumber;
    public List<int> doctorPatients;

    public doctor(){...};

    public doctor(string name, string surname, int age, string sex, int doctorID, Contacts c):base(name, surname, age, sex, c){...};

    public override string ToString(){...};
}

The problem is, when i'm trying to serialize class "doctor" into XML file with:

XmlSerializer SerializerDoc = new XmlSerializer(typeof(doctor));

foreach(doctor d in doctorList)
{
    TextWriter WriteFileStream = new StreamWriter("doctors/" + d.firstName + d.lastName + ".xml");
    SerializerDoc.Serialize(WriteFileStream, d);

    WriteFileStream.Close();
}

i get this error on line with creating a TextWriter (translation from russina's below):

"Необработанное исключение: System.InvalidOperationException: Clinic.doctor недос тупен в силу его уровня защиты. Возможна обработка только общих типов. в System.Xml.Serialization.TypeDesc.CheckSupported() в System.Xml.Serialization.TypeScope.GetTypeDesc(Type type, MemberInfo source , Boolean directReference, Boolean throwOnError) в System.Xml.Serialization.ModelScope.GetTypeModel(Type type, Boolean directR eference) в System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(Type type, XmlRootAttribute root, String defaultNamespace) в System.Xml.Serialization.XmlSerializer..ctor(Type type, String defaultNames pace) в System.Xml.Serialization.XmlSerializer..ctor(Type type) в Clinic.Clinic.saveDoctorInfo() в d:\Dropbox\CSharpHomeWork\ExamTask\Clinic\ Program.cs:строка 833 в Clinic.Clinic.launchMenu() в d:\Dropbox\CSharpHomeWork\ExamTask\Clinic\Prog ram.cs:строка 463 в Clinic.Program.Main(String[] args) в d:\Dropbox\CSharpHomeWork\ExamTask\Cli nic\Program.cs:строка 870 Press any key to continue . . ."

I have a russian version of WIN7, so the message on russian tells something like: "Unhandeled exception: .......: Clinic.doctor unavailable because of it's level of protection. It's possible to handle only a generic types." Translation's almost literal, so keep in mind.

Hope somebody will help me, because i can write class "doctor" with simple "XML Writer" but still it's none sense (as i think), as far as i can save it with one line, instead of 20.

Thanks guys.

Upadte: just did all of classes - public. Now i'm getting error on string: TextWriter WriteFileStream = new StreamWriter("doctors/" + d.firstName + d.lastName + ".xml");

It sais like: 

Unhandled exception: System.IO.DirectoryNotFoundException: Failed to find part of path "D:\Dropbox\CSharpHomeWork\ExamTask\Clinic\bin\Debug\doctors\Anders onNeo.xml".

Path is 100% correct. I just feel like instead of creating a file, it just tries to write something in already existing one.

BTW, sorry that i can't thank you with reputation up, because i can't do that now. But have my "verbal thanks" for now :)

Answer 1

The XmlSerializer can only serialize public classes and members. Either make the Doctor and all its base classes public class or use a different serializer (e.g. DataContractSerializer).