The innerException says:

-  InnerException {"'PROTOCOL-TYPE' is an invalid value for the 
XmlElementAttribute.DataType property. The property may only be specified 
for primitive types."} System.Exception {System.InvalidOperationException}

According to the documentation for DataType, it is about disambiguating the 
xsd type for primitive types only that map to CLR strings or are otherwise 
ambiguous.  It is not a way to specify CLR enums to XSD simpleType mappings.

But if you are just trying to rename the XSD type from PROTOCOL-TYPE to the 
CLR type PROTOCOLTYPEPOLICY, then use the TypeName attribute:

[System.Xml.Serialization.XmlTypeAttribute(TypeName="PROTOCOL-TYPE")]
public enum PROTOCOLTYPE {
    hugo,
    lulli,
}

And remove the DataType attribute all together.


"ankaiser" <ankaiser@d...> wrote in message 
news:16B8F083-F1A5-4546-B2FA-CC73874997B9@m......
> hello - i am just a beginner of xml,
>
> i want to produce the following xml-output:
>
> <PROTOCOL xsi:type="PROTOCOL-TYPE">hugo</PROTOCOL>
>
> with the following c#-source:
>
>    public enum PROTOCOLTYPEPOLICY
>    {
>        hugo,
>        lulli
>    }
>
>   [XmlElement(DataType = "PROTOCOLTYPEPOLICY")]
>   public PROTOCOLTYPEPOLICY PROTOCOL;
>
> why does it not work?
>