The WriteXml implementation you provide should write out the XML representation of the object. The framework writes a wrapper element and positions the XML writer after its start. Your implementation may write its contents, including child elements. The framework then closes the wrapper element.
Write sufficient information to the XmlWriter stream to allow the ReadXml method to reconstitute your object.
For example, if your object state includes an array variable, be sure to write the length of the array, or use a parent element to contain the elements that describe the array values, so that you know how many values to read when the object is reconstituted.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2