My XML
<?xml version="1.0" encoding="utf-8"?>
<metadata created="2014-05-15T12:26:07.701Z" xmlns="http://site/cu-2.0#" xmlns:ext="http://site/cu/b-2.0">
<customer-list count="47" offset="0">
<customer id="7123456" type="Cust" ext:mark="1">
<name>Tony Watt</name>
<sort-name>Watt, Tony</sort-name>
<gender>male</gender>
<country>US</country>
<knownAs-list>
<knownAs locale="ko" sort-name="Tony Watt"</knownAs>
<knownAs locale="ja" sort-name="Watt Tony"</knownAs>
</knownAs-list>
<tag-list>
<begin>Country</begin>
<tag count="1">
<name>usa</name>
</tag-list>
</customer>
<customer id="9876543" type="Cust" ext:mark="2">
....
</customer-list>
So i have some code that gets all the data. I went one step further to use Anonymous types and add the values into a class as below
Dim c = From cust As XElement In XDoc.Descendants(ns + "customer")
Select New Customer() With {.Name = cust.Element(ns + "name"),
.Surname = CStr(cust.Element(ns + "surname")),
.Id = cust.Attribute("id"),
.Tag = CStr(cust.Element("tag-list").Element("begin"))}
The above code returns data from the XML, but adding this line of code
.Tag = CStr(cust.Element("tag-list").Element("begin"))
throws an exception, "Object reference not set to an instance of an object". Now theres two possibilities here
I have my code wrong for that particular line (to retrieve 'begin' from the 'tag-list' element)
I know some tag-list elements dont have a nested begin element so that could be adding some confusion. I added Cstr to overcome this but not sure if this is enough?
After reading MSDN it seems using .Descendants (Xdoc.Descendants) would get the all the data from all elements where Elements would return data upto the path i have stated, so as far as i can tell the data 'should' be available with the above code. Could anyone assist me in getting the begin data from tag-list?
The XML namespace declaration is missing. Use
.Tag = CStr(cust.Element(ns + "tag-list").Element(ns + "begin"))
Related
I need to be able to extract individual nodes from this file into variables for further manipulation. I'm writing to the console to see what information is being pulled, but I am struggling to pull the name or description.
I can successfully print the entire file. I've tried getting individual nodes using placemark.<name>.Value and placemark.Element("name").Value, the second of which throws a NullReferenceException. Any ideas on how to be able to pull out the name and description in this instance?
Imports System.Xml
Imports System.Xml.Linq 'Visual Studio 2015 tells me this isn't needed
Imports System.Core 'Visual Studio 2015 tells me this isn't needed
Dim file As XDocument = XDocument.Load(filePath)
Dim placemarks As IEnumerable(Of XElement) = From test In file.Root.Elements()
For Each placemark As XElement In placemarks
Console.WriteLine(placemark) 'This works
Console.WriteLine(placemark.<name>.Value) 'This prints an empty line
Console.WriteLine(placemark.Element("description").Value) 'This throws a NullReferenceException
Next
This is the structure
<?xml version='1.0' encoding='UTF-8'?>
<kml xmlns='http://www.opengis.net/kml/2.2'>
<Document>
<name>Untitled layer</name>
<Placemark>
<name>Name 1</name>
<description>Description 1</description>
<ExtendedData>
<Data name='Test data one'>
<value>Test data 1</value>
</Data>
</ExtendedData>
<Point>
<coordinates>34725567547</coordinates>
</Point>
</Placemark>
<Placemark>
<name>Name 2</name>
<description>Description 2</description>
<ExtendedData>
<Data name='Test data two'>
<value>Test data 2</value>
</Data>
</ExtendedData>
<Point>
<coordinates>056795763767</coordinates>
</Point>
</Placemark>
If I have understood you correctly, you are trying to fetch the name & description present inside the PlaceMark node. But, since you are only fetching Root.Elements() your query will only fetch the complete XML starting from your root node.
You need to find the Descendants of PlaceMark node because you need to fetch the name & description inside it. Also, since the root node kml consists of namespace you need to specify that as well.
Here is the code:-
Dim ns As XNamespace = "http://www.opengis.net/kml/2.2"
Dim placeMarks = From test In file.Root.Element(ns + "Document")
.Descendants(ns + "Placemark") Select test
For Each pm In placeMarks
Console.WriteLine("Name: {0}", pm.Element(ns + "name").Value)
Console.WriteLine("Description: {0}", pm.Element(ns + "description").Value)
Console.WriteLine()
Next
I am getting following output:-
I'm looking for the best way to parse GML to return the spatial data. As example here's a GML file:
<?xml version="1.0" encoding="utf-8"?>
<gml:FeatureCollection xmlns:gml="http://www.opengis.net/gml"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:onecallgml="http://www.pelicancorp.com/onecallgml"
xsi:schemaLocation="http://www.pelicancorp.com/onecallgml http://www.pelicancorp.com/digsafe/onecallgml.xsd">
<gml:featureMember>
<onecallgml:OneCallReferral gml:id="digsite">
<onecallgml:LocationDetails>
<gml:surfaceProperty>
<gml:Polygon srsName="EPSG:2193">
<gml:exterior>
<gml:LinearRing>
<gml:posList>
1563229.00057526 5179234.72234694 1563576.83066077 5179352.36361939 1563694.22647617 5179123.23451613 1563294.42782719 5179000.13697214 1563229.00057526 5179234.72234694
</gml:posList>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</gml:surfaceProperty>
</onecallgml:LocationDetails>
</onecallgml:OneCallReferral>
</gml:featureMember>
</gml:FeatureCollection>
How do I iterate through each featureMember, and then its polygon(s) and then get the posList coordinates into an array?
When dealing with XML in VB.NET, I recommend using LINQ to XML. You will probably want to extract more information (e.g. something to tie back to the featureMember), but a simple example could be:
' You will need to import the XML namespace
Imports <xmlns:gml = "http://www.opengis.net/gml">
...
Dim xml As XElement = XElement.Parse(myGmlString) ' or some other method
Dim polys = (
From fm In xml...<gml:featureMember>
From poly In fm...<gml:Polygon>
Select New With {
.Name = poly.#srsName,
.Coords = (poly...<gml:posList>.Value.Trim() _
.Split({" "}, StringSplitOptions.RemoveEmptyEntries) _
.Select(Function(x) CDbl(x))).ToArray()
}
).ToList()
This will give you a List of anonymous types with the polygon name and the coordinates as an array of Double.
I'm seeing some unusual behavior when using the DataContractSerializer. I have defined a message contract like so:
namespace MyNamespace.DataContracts
{
[MessageContract(WrapperName = "order", WrapperNamespace = #"http://example.com/v1/order")]
public class MyOrder
{
[MessageBodyMember(Namespace = #"http://example.com/v1/order", Order = 1)]
public MyStore store;
[MessageBodyMember(Namespace = #"http://example.com/v1/order", Order = 2)]
public MyOrderHeader orderHeader;
[MessageBodyMember(Namespace = #"http://example.com/v1/order", Order = 3)]
public List<MyPayment> payments;
[MessageBodyMember(Namespace = #"http://example.com/v1/order", Order = 4)]
public List<MyShipment> shipments;
}
.
.
I'm sending it an XML message that looks like this:
<?xml version="1.0" encoding="utf-8"?>
<order xmlns="http://example.com/v1/order>
<store>
...
</store>
<orderHeader>
...
</orderHeader>
<payments>
<payment>
...
</payment>
</payments>
<shipments>
<shipment>
...
</shipment>
</shipments>
</order>
My service deserializes this XML as expected. Inside my service, I'm using the DataContractSerializer to create an XML string and that's where things get weird. I'm using the serializer like this:
DataContractSerializer serializer = new DataContractSerializer(typeof(MyOrder));
using (MemoryStream ms = new MemoryStream())
{
serializer.WriteObject(ms, order);
ms.Position = 0;
StreamReader sr = new StreamReader(ms);
string outputMessage = sr.ReadToEnd();
}
Once this finishes, the outputMessage contains the following XML:
<?xml version="1.0" encoding="utf-8"?>
<MyOrder xmlns="http://example.com/v1/order" xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
<order>
<store>
...
</store>
<orderHeader>
...
</orderHeader>
<payments>
<payment>
...
</payment>
</payments>
<shipments>
<shipment>
...
</shipment>
</shipments>
</order>
</MyOrder>
Needless to say, anything expecting to receive the original XML message will fail to parse this. So I guess I have two questions:
Why is the DataContractSerializer
adding the extra outer node to my
XML output?
Is there a way to stop it from doing
this?
Thanks.
I should probably add this is with .NET 4.
You could try using WriteObjectContent instead of WriteObject, but I'm unable to reproduce your problem using the code you supplied. All the extra class defintions that are part of your message contract are empty in my definition, but this is the XML I am getting:
<MyOrder xmlns="http://schemas.datacontract.org/2004/07/SandboxApp"
xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
<orderHeader i:nil="true"/>
<payments i:nil="true"/>
<shipments i:nil="true"/>
<store i:nil="true"/>
</MyOrder>
Which also seems odd, since it seems to ignore the WrapperName. Same result in .NET 3.5 SP1 and .NET 4.0.
I am trying to read this XML document.
An excerpt:
<datafile xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="wiitdb.xsd">
<WiiTDB version="20100217113738" games="2368"/>
<game name="Help Wanted: 50 Wacky Jobs (DEMO) (USA) (EN)">
<id>DHKE18</id>
<type/>
<region>NTSC-U</region>
<languages>EN</languages>
<locale lang="EN">
<title>Help Wanted: 50 Wacky Jobs (DEMO)</title>
<synopsis/>
</locale>
<developer>HUDSON SOFT CO., LTD.</developer>
<publisher>Hudson Entertainment, Inc.</publisher>
<date year="2009" month="" day=""/>
<genre>party</genre>
<rating type="ESRB" value="E10+">
<descriptor>comic mischief</descriptor>
<descriptor>mild cartoon violence</descriptor>
<descriptor>mild suggestive themes</descriptor>
</rating>
<wi-fi players="0"/>
<input players="2">
<control type="wiimote" required="true"/>
<control type="nunchuk" required="true"/>
</input>
<rom version="" name="Help Wanted: 50 Wacky Jobs (DEMO) (USA) (EN).iso" size="4699979776"/>
</game>
So far I have this:
Dim doc as XPathDocument
Dim nav as XPathNavigator
Dim iter as XPathNodeIterator
Dim lstNav As XPathNavigator
Dim iterNews As XPathNodeIterator
doc = New XPathDocument("wiitdb.xml")
nav = doc.CreateNavigator
iter = nav.Select("/WiiTDB/game") 'Your node name goes here
'Loop through the records in that node
While iter.MoveNext
'Get the data we need from the node
lstNav = iter.Current
iterNews = lstNav.SelectDescendants(XPathNodeType.Element, False)
'Loop through the child nodes
txtOutput.Text = txtOutput.Text & vbNewLine & iterNews.Current.Name & ": " & iterNews.Current.Value
End While
It just skips the "While iter.MoveNext" part of the code. I tries it with a simple XML file, and it works fine.
I think your XPath query is off. WiiTDB is a closed node, so you need to look for /datafile/game or //game.
Use the System.Xml.Serialization namespace instead: create a dedicated, serializable class to hold the data you wish to load and define shared serialize / deserialize functions with strongly typed arguments to do the work for you.
As the structure of the new classes will closely follow that of your XML data, there should be no confusion as to which data is located where within a run time instance.
See my answer here for an idea of how to create a class from an example XML file.
I've been using XML serialization for a while, and today I realized something really odd. If I have a new line right after a "dot" (.), when i deserialize, I lose the dot. Has anyone ever had this happen to them? The following is my serialization code:
Serialize
Dim xmlSerializer As New System.Xml.Serialization.XmlSerializer(GetType(SilverWare.Licensing.Common.StoreLicense), New System.Type() {GetType(SilverWare.Licensing.Common.StationLicense)})
Dim gen As LicenseGenerator
If store Is Nothing Then
Throw New ArgumentNullException("store")
ElseIf store.StationLicenses Is Nothing Then
Throw New ArgumentNullException("store.StationLicenses")
ElseIf store.StationLicenses.Length = 0 Then
Throw New ArgumentOutOfRangeException("store.StationLicenses", "Must contain at least one element.")
End If
' Create a license generator for issuing new license keys.
gen = New LicenseGenerator(store)
' Generate store key.
store.LicenseKey = gen.GenerateLicenseKey
' Generate individual station keys.
For Each station In store.StationLicenses
station.LicenseKey = gen.GenerateLicenseKey(station)
Next
' Write license to file.
Using xFile As Xml.XmlWriter = Xml.XmlWriter.Create(licenseFile)
xmlSerializer.Serialize(xFile, store)
xFile.Close()
End Using
Deserialize
Dim xmlDeserializer As New System.Xml.Serialization.XmlSerializer(GetType(SilverWare.Licensing.Common.StoreLicense), New System.Type() {GetType(SilverWare.Licensing.Common.StationLicense)})
Dim result As SilverWare.Licensing.Common.StoreLicense
Using xFile As Xml.XmlReader = Xml.XmlReader.Create(licenseFile)
result = DirectCast(xmlDeserializer.Deserialize(xFile), SilverWare.Licensing.Common.StoreLicense)
xFile.Close()
End Using
Return result
The really funny part is that if I have a space after the dot, or remove the new line character, there are no problems. This only happens if it is dot which I find mind boggling.
Here is a quick sample of my XML file that was created when I serialized:
<?xml version="1.0" encoding="utf-8" ?>
<StoreLicense xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
...
<ReceiptAddress>98 N. Washington St.
Berkeley Springs West Virginia</ReceiptAddress>
<Name>Ambrae House at Berkeley Springs</Name>
<AliasName>Ambrae House</AliasName>
<Address1>98 N. Washington St.</Address1>
<Address2 />
...
</StoreLicense>
The line that is having the problem is the ReceiptAddress Node.
This post on MSDN seems to answer your question.
MSDN: Serialize String containing only whitespace such as a " " character
From that post, try this:
<XmlAttribute("xml:space")> _
Public SpacePreserve As [String] = "preserve"
This creates a root node like the following:
<DataImportBase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema" xml:space="preserve">
Jim
Since I was using someone elses dll, I didn't even think that it would be modifying my data when we imported it. What was happening was that the other programmer had a reg_ex that was looking for a dot before a new line. That was my issue, and my grief for 3 months.