How to write data in xml file wp8

Question

I have add one xml file in Assets folder This is Empty and when i try to add list data in xml file this return a error. error show in images please check the image . here i have attach a image . Please Help me This is my code

public void BookmarkPage()
    {
        List<Bookmarkdata> data = new List<Bookmarkdata>();
        data.Add(new Bookmarkdata() { Bookname = "Kate", Bookid = "Brown", BookPath = "Brown", Pageno = 25 });
        data.Add(new Bookmarkdata() { Bookname = "Tom", Bookid = "Stone", BookPath = "Brown", Pageno = 63 });
        data.Add(new Bookmarkdata() { Bookname = "Michael", Bookid = "Liberty", BookPath = "Brown", Pageno = 37 });
        AddXml(data);

    }

private void AddXml(List<Bookmarkdata> data)
{

    XmlWriterSettings xmlWriterSettings = new XmlWriterSettings();
    xmlWriterSettings.Indent = true;
    using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
    {
        using (IsolatedStorageFileStream stream = myIsolatedStorage.OpenFile("BookmarkFile.xml", FileMode.Create))
        {
            XmlSerializer serializer = new XmlSerializer(typeof(List<Bookmarkdata>));
            using (XmlWriter xmlWriter = XmlWriter.Create(stream, xmlWriterSettings))
            {
                serializer.Serialize(xmlWriter, data);
            }
        }
    }

This is my class

 class Bookmarkdata
{
    string bookname;
    string bookid;
    string bookPath;
    int pageno;


    public string Bookname
    {
        get { return bookname; }
        set { bookname = value; }
    }

    public string Bookid
    {
        get { return bookid; }
        set { bookid = value; }
    }
    public string BookPath
    {
        get { return bookPath; }
        set { bookPath = value; }
    }

    public int Pageno
    {
        get { return pageno; }
        set { pageno = value; }
    }
}

}

Here i attach a error image in visual studio

Answer 1

As the error message suggested, Bookmarkdata class is inaccessible due to it's protection level. You need to simply set it's access modifier to public :

public class Bookmarkdata
{
    .........
    .........
}

and XmlSerializer will be able to serialize your list smoothly :)