How do I serialize DateTime properly?

When I XML-serialize my DateTime field (which has the value from a datepicker), the date is always serialized as

0001-01-01T00:00:00

i.e. 1st January 1AD. Why is this? Also, when I try to deserialize the XML, I get this error:

startIndex cannot be larger than length of string.

Parameter name: startIndex.

However, when I edit the XML manually, deserialization goes just fine for years 1000-9999, but not for years <1000 ?

The DateTime property has the [XmlElement], just like all other fields that get serialized properly, and the rest of the code appears to be ok. Thanks in advance!

If you want to serialize it easily (and masterize the serialization of it), use a proxy field.

[Serializable]
public class Foo
{
    // Used for current use
    [XmlIgnore]
    public DateTime Date { get; set; }

    // For serialization.
    [XmlElement]
    public String ProxyDate
    {
        get { return Date.ToString("<wanted format>"); }
        set { Date = DateTime.Parse(value); }
    }
}

Edit

The following code :

[Serializable]
public class TestDate
{
    [XmlIgnore]
    public DateTime Date { get; set; }

    [XmlElement]
    public String ProxyDate
    {
        get { return Date.ToString("D"); }
        set { Date = DateTime.Parse(value); }
    }
}

public class Program
{
    static void Main(string[] args)
    {
        TestDate date = new TestDate()
        {
            Date = DateTime.Now
        };

        XmlSerializer serializer = new XmlSerializer(typeof(TestDate));
        serializer.Serialize(Console.Out, date);
    }
}

produces the following output:

<?xml version="1.0" encoding="ibm850"?>
<TestDate xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http:
//www.w3.org/2001/XMLSchema">
  <ProxyDate>mardi 14 juin 2011</ProxyDate>
</TestDate>