Question

When I add an “XmlAttribute/XmlElement” to a property in an Interface and 100 other classes inherit from this interface, when Serializing the object to XML – why doesn’t the attributename I entered show up in the XML file after serialization?

interface Test
{
    [XmlAttribute("Name")]
    bool PropertyName { get; set; }
}

when saving the file, is shows “PropertyName” and not “Name”.

Is there any way to make it work, so a proeprty with an XmlAttributes added to an interface changes the Value everywhere instead of Value because if a few classes inherit from the same interface it takes alot of time to add all those Attributes to all those classes that inherit it, and it would be easier to change the Name of the Attribute instead of changing a 100 of them.

Answer 1

Deukalin, spent some time and make it work with comprehensive tree of classes and interfaces.

Here is the working code

    public interface ITestX
    {
        [XmlAttribute("NameX")]
        string PropertyNameX { get; set; }
    }

    public interface ITestY
    {
        [XmlAttribute("NameY")]
        string PropertyNameY { get; set; }
    }

    public interface ITestZ
    {
        [XmlAttribute("NameZ")]
        string PropertyNameZ { get; set; }
    }

    public abstract class TestC : ITestZ
    {
        public abstract string PropertyNameZ { get; set; }
    }

    public abstract class TestA : TestC, ITestX, ITestY
    {
        public abstract string PropertyNameX { get; set; }
        public abstract string PropertyNameY { get; set; }
    }

    public class TestB : TestA
    {
        public override string PropertyNameX { get; set; }
        public override string PropertyNameY  { get; set; }
        public override string PropertyNameZ { get; set; }
    }

    public static class ClassHandler
    {
        public static T GetCustomAttribute<T>(this PropertyInfo propertyInfo, bool inherit) where T : Attribute
        {
            object[] attributes = propertyInfo.GetCustomAttributes(typeof(T), inherit);

            return attributes == null || attributes.Length == 0 ? null : attributes[0] as T;
        }

        public static void GetXmlAttributeOverrides(XmlAttributeOverrides overrides, Type type)
        {
            if (type.BaseType != null)
            {
                GetXmlAttributeOverrides(overrides, type.BaseType);
            }

            foreach (Type derived in type.GetInterfaces())
            {
                foreach (PropertyInfo propertyInfo in derived.GetProperties())
                {
                    XmlAttributeAttribute xmlAttributeAttribute = ClassHandler.GetCustomAttribute<XmlAttributeAttribute>(propertyInfo, true) as XmlAttributeAttribute;

                    if (xmlAttributeAttribute == null)
                        continue;

                    XmlAttributes attr1 = new XmlAttributes();
                    attr1.XmlAttribute = new XmlAttributeAttribute();
                    attr1.XmlAttribute.AttributeName = xmlAttributeAttribute.AttributeName;
                    overrides.Add(type, propertyInfo.Name, attr1);
                }
            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            XmlAttributeOverrides XmlAttributeOverrides = new XmlAttributeOverrides();
            ClassHandler.GetXmlAttributeOverrides(XmlAttributeOverrides, typeof(TestB));
            try
            {
                TestB xtest = new TestB() { PropertyNameX = "RajX", PropertyNameY = "RajY", PropertyNameZ = "RajZ" };

                StringBuilder xmlString = new StringBuilder();
                using (XmlWriter xtw = XmlTextWriter.Create(xmlString))
                {
                    XmlSerializer serializer = new XmlSerializer(typeof(TestB), XmlAttributeOverrides);
                    serializer.Serialize(xtw, xtest);

                    xtw.Flush();
                }

                Console.WriteLine(xmlString.ToString());
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
}

Below is the output of sample above

<?xml version="1.0" encoding="utf-16"?><TestB xmlns:xsi="http://www.w3.org/2001/
XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" NameZ="RajZ" Na
meX="RajX" NameY="RajY" />
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