C# XML Deserialization with multiple namespaces and namespace prefixes

Question

I'm pretty sure this has been asked and answered I just can't find it

I'm trying to deserialize XML into POCOs.
This is the part im struggling with

<Trias version="1.1" xmlns="http://www.vdv.de/trias" xmlns:siri="http://www.siri.org.uk/siri"

This is my entire XML:

<?xml version="1.0" encoding="UTF-8"?>
<Trias version="1.1" xmlns="http://www.vdv.de/trias" xmlns:siri="http://www.siri.org.uk/siri" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ServiceRequest>
<siri:RequestTimestamp>2012-10-28T20:56:00Z</siri:RequestTimestamp>
<siri:RequestorRef>SEUS</siri:RequestorRef>
<RequestPayload>
<TripRequest>
<Origin>
<LocationRef>
<StopPointRef>8500320</StopPointRef>
</LocationRef>
<DepArrTime>2018-10-09T08:05:51</DepArrTime>
</Origin>
<Destination>
<LocationRef>
<StopPointRef>8500322</StopPointRef>
</LocationRef>
<DepArrTime>2018-10-09T08:05:51</DepArrTime>
</Destination>
<Params>
<NumberOfResults>1</NumberOfResults>
<IncludeTrackSections>true</IncludeTrackSections>
<IncludeLegProjection>true</IncludeLegProjection>
<IncludeIntermediateStops>true</IncludeIntermediateStops>
</Params>
</TripRequest>
</RequestPayload>
</ServiceRequest>
</Trias>

How do I model the xmlns:siri in C#? My Class looks like this:

[XmlRoot(nameof(Trias), Namespace = "http://www.vdv.de/trias")]
public class Trias
{

    [XmlAttribute("version")]
    public string Version { get; set; }

    [XmlAttribute("xmlns")]
    public string Xmlns { get; set; }

    [XmlAttribute("siri")]
    public string Siri { get; set; }
}

Answer 1

Try to change your XmlAttribute for property Siri from [XmlAttribute("siri")] to [XmlAttribute(Namespace = "http://www.siri.org.uk/siri")]

[XmlRoot(nameof(Trias), Namespace = "http://www.vdv.de/trias")]
public class Trias
{

    [XmlAttribute("version")]
    public string Version { get; set; }

    [XmlAttribute("xmlns")]
    public string Xmlns { get; set; }

    [XmlAttribute(Namespace = "http://www.siri.org.uk/siri")]
    public string Siri { get; set; }
}