XmlSerialization throwing error when deserializing?

Question

I am trying to serialize an object into the database using xml serialization, however when deserializing it I am getting an error.

The error is There is an error in XML document (2, 2) with an inner exception of "<MyCustomClass xmlns=''> was not expected."

The code I am using to serialize is:

public static string SerializeToXml<T>(T obj)
{
    if (obj == null)
        return string.Empty;

    StringWriter xmlWriter = new StringWriter();
    XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));
    xmlSerializer.Serialize(xmlWriter, obj);
    return xmlWriter.ToString();
}

public static T DeserializeFromXml<T>(string xml)
{
    if (xml == string.Empty)
        return default(T);

    T obj;
    XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));
    StringReader xmlReader = new StringReader(xml);
    obj = (T)xmlSerializer.Deserialize(xmlReader);
    return obj;
}

The SerializedXml begins with:

<?xml version="1.0" encoding="utf-16"?>
<MyCustomClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">

This is my first time using serialization and I'm wondering what I'm doing something wrong with my code.

As an aside, normally `xmlReader` and `xmlWriter` would be used for instances of `XmlReader` and `XmlWriter`, not `StringReader` and `StringWriter`. — Steven Sudit, Aug 18 '10 at 19:59
To solve this, I think we'll need to see the declaration of `MyCustomClass`, as well as the rest of the XML. — Steven Sudit, Aug 18 '10 at 19:59
It is telling me I can't create an instance of the abstract class XmlWriter — Rachel, Aug 18 '10 at 20:01
My equivalent code works good. Can you serialize empty class? Then add some properties to it. — alxx, Aug 18 '10 at 20:07
The MyCustomClass code is fairly long... it contains no attributes other then `[Serializable]` and its only property is a CustomObservableCollection (inherited from base ObservableCollection) of CustomObjects. — Rachel, Aug 18 '10 at 20:07
@Rachel: please don't put tags like "C#" in your title. It's enough to have them in your tags. — John Saunders, Aug 18 '10 at 20:08
Would I be correct in thinking your XML does't actually say but rather since the quotes aren't supposed to be escaped like that in the XML but if you copied it out of a debugger window it would be. If so will you or someone edit it for clarity? — Peter T. LaComb Jr., Aug 18 '10 at 20:14

score 1 · Answer 1 · answered Aug 18 '10 at 20:10

1

BTW, you need using blocks around your code:

using (StringReader reader = new StringReader(xml))
{
    obj = (T)xmlSerializer.Deserialize(reader);
}

answered Aug 18 '10 at 20:10

John Saunders

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score 1 · Answer 2 · answered Aug 19 '10 at 12:05

1

Unfortunately, XmlSerialization exceptions is a piece of crap.

You normally have to drill down into countless levels of inner exceptions to get to the real error.

answered Aug 19 '10 at 12:05

leppie

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I will keep that in mind when doing any other debugging, Thanks – Rachel Aug 19 '10 at 12:09

score 1 · Accepted Answer · answered Aug 19 '10 at 12:08

I'm sorry, I just realized my problem was stupidity =/

I was serializing the class but trying to deserialize the ObservableCollection only. Once I changed that to serializing/deserialing the correct object it works great, although I thank you for the tip about using blocks

XmlSerialization throwing error when deserializing?

3 Answers3