How to serialize Xml Date only from DateTime in C#

Question

I've the following simple class;

Birthdays
{
  public DateTime DateOfBirth {get;set;}
  public string Name {get;set;}
}

I then serialise my object to Xml using;

try
{
   XmlSerializer serializer = new XmlSerializer(obj.GetType());

   using (MemoryStream ms = new MemoryStream())
   {
        XmlDocument xmlDoc = new XmlDocument();

        serializer.Serialize(ms, obj);
        ms.Position = 0;
        xmlDoc.Load(ms);
        return xmlDoc;
    }
}
catch (Exception e)
{
    ....
}

The problem I have is that when the Xml is returned the DateOfBirth format is like 2012-11-14T00:00:00 and not 2012-11-14.

How can I override it so that I'm only returning the date part ?

Solution

You should use the XmlElementAttribute.DataType property and specify date.

public class Birthdays
{
  [XmlElement(DataType="date")]
  public DateTime DateOfBirth {get;set;}
  public string Name {get;set;}
}

Using this outputs

<?xml version="1.0" encoding="utf-16"?>
<Birthdays xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <DateOfBirth>2013-11-14</DateOfBirth>
  <Name>John Smith</Name>
</Birthdays> 

Another option is to use a string property just for serialization (backed by a DateTime property you use), as at Force XmlSerializer to serialize DateTime as 'YYYY-MM-DD hh:mm:ss' (this is needed for DataContractSerializer, where the xs:date type is not as well-supported)

Comments

[Ole Albers]

(second part:) Would cut off any existing time, but still "dateTime" has the 00:00 Time. Would not change a thing.

[terrybozzio]

thats why i commented use datetime.Date.

[Ole Albers]

But still: The xml would look just like before

[terrybozzio]

if the problem is in wants serialized then not mine not yours but tim S.(for a single property result i mean).my answer is to not rewrite the class(although it is the best solution),and just "get" the desired formatt.

[Ole Albers]

better than my answer I have to admit :)

[Chuck Savage]

Helped me get there for XElement save of just the date, thanks.