Develop Reference

Sequence contains no elements when trying to grab xml node value from xml string

Please read the code bellow. There I am trying to grab all elements under the <GetSellerListResponse> node, then my goal is to grab TotalNumberOfPages value (currently it's 9 as you can see in the XML).
But my problem is I am getting an error:
System.InvalidOperationException: 'Sequence contains no elements'
Error screenshot is attached for better understanding. Can you tell me what's wrong the way I am trying to grab all elements? Also if possible can you tell how I can grab that 9 from TotalNumberOfPage?
Thanks in advance
C#:
var parsedXML = XElement.Parse(xml);
var AllElements = parsedXML.Descendants("GetSellerListResponse")
.Where(x => x.Attribute("xmlns").Value.Equals("urn:ebay:apis:eBLBaseComponents"))
.First();
XML:
<?xml version="1.0" encoding="UTF-8"?>
<GetSellerListResponse xmlns="urn:ebay:apis:eBLBaseComponents">
<Timestamp>2018-06-20T17:26:29.518Z</Timestamp>
<Ack>Success</Ack>
<Version>1059</Version>
<Build>E1059_CORE_APISELLING_18694654_R1</Build>
<PaginationResult>
<TotalNumberOfPages>9</TotalNumberOfPages>
</PaginationResult>
</GetSellerListResponse>

EDIT: your mistake is the usage of XElement: it is searching for matching elements in the children of <GetSellerListResponse>; that's why you are not getting any result. Change XElement.Parse(xml); to XDocument.Parse(xml);, then the following snippets will work.
You could simply check for the local name:
var AllElements = parsedXML.Descendants().First(x => x.Name.LocalName == "GetSellerListResponse");
I would suggest to use XDocument instead of XElement for parsedXML, because you could shorten the above query to var AllElements = parsedXML.Root;
Another thing you could try is prepending the namespace:
XNamespace ns = "urn:ebay:apis:eBLBaseComponents";
var AllElements = parsedXML.Descendants(ns + "GetSellerListResponse").First();
To answer the question "how to get the number of pages":
var pages = AllElements.Element(ns + "PaginationResult").Element(ns + "TotalNumberOfPages").Value;

I would suggest using the XmlDocument class from System.Xml.
Try the code below:
XmlDocument doc = new XmlDocument();
doc.LoadXml("<GetSellerListResponse xmlns=\"urn:ebay:apis:eBLBaseComponents\"><Timestamp>2018-06-20T17: 26:29.518Z</Timestamp><Ack>Success</Ack><Version>1059</Version><Build>E1059_CORE_APISELLING_18694654_R1</Build><PaginationResult><TotalNumberOfPages>9</TotalNumberOfPages></PaginationResult></GetSellerListResponse>");
XmlNodeList nodeList = doc.GetElementsByTagName("TotalNumberOfPages");
In this case, your nodeList will have just the one element for TotalNumberOfPages and you can access the value by checking
nodeList.FirstOrDefault().InnerText

Tricky to read XML from web service C#

I have looked everywhere, and cannot find anything to help me.
I am writing a program that connects to a webservice and then the webservice sends an XML response. After the response is received I have to retrieve certain values from it, but this is where it gets tricky
Here is a snippet of the returned XML:
<?xml version="1.0"?>
<MobilePortalSellingCategoriesHierarchy xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<Response xmlns="http://blabla.com/service/">Successful</Response>
<ResponseNumber xmlns="http://blabla.com/service/">0</ResponseNumber>
<SellingCategoriesHierarchy xmlns="http://tym2sell.com/PortalService/">
<Response>Successful</Response>
<ResponseNumber>0</ResponseNumber>
<SellingCategories>
<PortalSellingCategory>
<SellingCategoryId xsi:nil="true" />
<SellingCategoryName>category1</SellingCategoryName>
<DeliveryMethod />
<DeliveryMethodNumber>0</DeliveryMethodNumber>
<SellingCategories>
<PortalSellingCategory>
<SellingCategoryId xsi:nil="true" />
<SellingCategoryName>category1_Item</SellingCategoryName>
<DeliveryMethod />
<DeliveryMethodNumber>0</DeliveryMethodNumber>
<SellingCategories>
<PortalSellingCategory>
<SellingCategoryId>2</SellingCategoryId>
<SellingCategoryName>Item2</SellingCategoryName>
<DeliveryMethod>Display</DeliveryMethod>
<DeliveryMethodNumber>1</DeliveryMethodNumber>
<VoucherValue>0.00</VoucherValue>
<IsVariablePrice>true</IsVariablePrice>
<MinimumVoucherValue>1.00</MinimumVoucherValue>
<MaximumVoucherValue>1000.00</MaximumVoucherValue>
<VoucherValueIncrement>1.00</VoucherValueIncrement>
<AdditionalInputItems>
<PortalAdditionalInputItem>
<InputItemId>-1</InputItemId>
<Label>Value:</Label>
<IsNumericOnly>true</IsNumericOnly>
<MaximumLength>7</MaximumLength>
<Hidden>false</Hidden>
</PortalAdditionalInputItem>
<PortalAdditionalInputItem>
<InputItemId>4</InputItemId>
<Label>Mobile Number</Label>
<IsNumericOnly>true</IsNumericOnly>
<MaximumLength>15</MaximumLength>
<Hidden>false</Hidden>
</PortalAdditionalInputItem>
</AdditionalInputItems>
<TwoStep>false</TwoStep>
<SelectedIcon>SamplePicture</SelectedIcon>
<UnSelectedIcon>SamplePicture</UnSelectedIcon>
This repeats from the SellingCategories node just under Response for a couple of times.
Here is a Snippet of my code where I get the XML as string.
XmlDocument xml = new XmlDocument();
xml.LoadXml(receivedData);
XmlNodeList xnList = xml.SelectNodes("/MobilePortalSellingCategoriesHierarchy");
foreach (XmlNode xn in xnList)
{
string sellingCategoryName = xn["SellingCategoryName"].InnerText;
string SelectedIcon = xn["SelectedIcon"].InnerText;
string UnSelectedIcon = xn["UnSelectedIcon"].InnerText;
richTextBox1.AppendText(string.Format("Name: {0} {1} {2}", sellingCategoryName, SelectedIcon, UnSelectedIcon));
}
I have tried changing xml.SelectNodes("/MobilePortalSellingCategoriesHierarchy");
to
xml.SelectNodes("/MobilePortalSellingCategoriesHierarchy/SellingCategoriesHierarchy/SellingCategories/PortalSellingCategory");
I need to select each SellingCategoryName and list the SellingCategoryName(s) and all the other items underneath it.
I was hoping to get something in the lines of:
Category1
Category1_Item
Item2
SamplePicture
Sample Picture
Mine only reads the First Node and then returns "Successful" to me.
I havve also tried:
XElement root = XElement.Load("FilePath");
var sellingCategoryNames = from PortalSellingCategory in root.Elements("MobilePortalSellingCategoriesHierarchy")
where (string)PortalSellingCategory.Element("SellingCategoriesHierarchy").Element("SellingCategories").Element("PortalSellingCategory") != ""
select PortalSellingCategory;
foreach (var xEle in sellingCategoryNames)
{
richTextBox1.Text = (string)xEle;
}
Any help would be greatly appreciated.

What you are doing with
xml.SelectNodes("/MobilePortalSellingCategoriesHierarchy");
is selecting your root node, which is just one. Thats why you only get one item in your list back. Is the hierarchy important? I can see that PortalSellingCategory can also be inside another PortalSellingCategory. If not maybe you could try the following select:
xml.SelectNodes("//PortalSellingCategory");
This will search for every node named "PortalSellingCategory" in your response, no mather where in the hierarchy it is.
EDIT:
And yes, you should look out for the namespaces, sry for didnt seeing that.
If you like geeting all the nodes with XPath you must create a new NamespaceManager and at it to your selectNodes call:
XmlDocument xml = new XmlDocument();
xml.LoadXml(data);
XmlNamespaceManager ns = new XmlNamespaceManager(xml.NameTable);
ns.AddNamespace("ns", "http://tym2sell.com/PortalService/");
XmlNodeList xnList = xml.SelectNodes("//ns:PortalSellingCategory", ns);

I would use XElement instead of XMLDocument, and then use Linq to query or pick the elmements like: XElement xContact = ....
int contactno = (int?)xContact.Element("command").Element("contactperson").Attribute("contactpersonid") ?? -1;
if (xContact.Element("command").Element("contactperson").Element("name").Element("firstname") != null)
console.writeline(xContact.Element("command").Element("contactperson").Element("name").Element("firstname").Value);

var doc= new XmlDocument();
doc.Load("FilePath");
var nodeList = xml.GetElementsByTagName("PortalSellingCategory");
Hi,
It returns the collection of nodes, and you just have to query it to get needed informations.
Feel free to ask help if needed.
Dimitri.

I'm unable to extract the Data from this XML

I'm currently working on a small weather application in C#. To do this, I need to extract data from this xml file: http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20geo.places%20where%20text%3D%22london%22&format=xml
In this specific case I need the value of the first /query/results/place/woeid node. I've been looking around and tried many different methods, but didn't manage to get any values with any of those. My current code looks like this:
string query = String.Format("http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20geo.places%20where%20text%3D%22london%22&format=xml");
XmlDocument xml = new XmlDocument();
xml.Load(query);
XmlNodeList nodeList = wData.DocumentElement.SelectNodes("/query/results/place");
foreach (XmlNode node in nodeList)
{
return node.SelectSingleNode("woeid").InnerText;
}
return "NO WOEID FOUND!";
I'm just starting to learn C# so I might do some stupid mistakes. Still, I would really appreciate any kind of help.

You can use XDocument
string query = String.Format("http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20geo.places%20where%20text%3D%22london%22&format=xml");
XDocument xml = XDocument.Load(query);
XNamespace ns = "http://where.yahooapis.com/v1/schema.rng";
var woeid = xml.Element("query").Element("results").Elements(ns + "place").FirstOrDefault().Element(ns +"woeid").Value;
Make sure you check if there are any elements in the XDocuments

Read first root node from XML

I work with three kinds of XML files :
Type A:
<?xml version="1.0" encoding="UTF-8"?>
<nfeProc versao="2.00" xmlns="http://www.portalfiscal.inf.br/nfe">
</nfeProc>
Tyepe B:
<?xml version="1.0" encoding="UTF-8"?>
<cancCTe xmlns="http://www.portalfiscal.inf.br/cte" versao="1.04">
</cancCTe>
Type C:]
<?xml version="1.0" encoding="UTF-8"?>
<cteProc xmlns="http://www.portalfiscal.inf.br/cte" versao="1.04">
</cteProc>
I have try with this code to read the first node :
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(#"C:\crruopto\135120068964590_v01.04-procCTe.xml");
XmlNodeList ml = xmlDoc.GetElementsByTagName("*");
XmlElement root = xmlDoc.DocumentElement;
exti = root.ToString();
but dont return anything i want to read the first node , need to know if the file is nfeProc ,canCTE or cteProc
The second question is how i get the value from "value" in the same tag???
Thanks

From this post:
//Root node is the DocumentElement property of XmlDocument
XmlElement root = xmlDoc.DocumentElement
//If you only have the node, you can get the root node by
XmlElement root = xmlNode.OwnerDocument.DocumentElement

I would suggest using XPath. Here's an example where I read in the XML content from a locally stored string and select whatever the first node under the root is:
XmlDocument doc = new XmlDocument();
doc.Load(new StringReader(xml));
XmlNode node = doc.SelectSingleNode("(/*)");

If you aren't required to use the XmlDocument stuff, then Linq is your friend.
XDocument doc = XDocument.Load(#"C:\crruopto\135120068964590_v01.04-procCTe.xml");
XElement first = doc.GetDescendants().FirstOrDefault();
if(first != null)
{
//first.Name will be either nfeProc, canCTE or cteProc.
}

Working with Linq to XML is the newest and most powerful way of working with XML in .NET and offers you a lot more power and flexibility than things like XmlDocument and XmlNode.
Getting the root node is very simple:
XDocument doc = XDocument.Load(#"C:\crruopto\135120068964590_v01.04-procCTe.xml");
Console.WriteLine(doc.Root.Name.ToString());
Once you have constructed an XDocument you don't need to use any LINQ querying or special checking. You simply pull the Root property from the XDocument.

Thanks i have solved this way the first part
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(nomear);
XmlNodeList ml = xmlDoc.GetElementsByTagName("*");
XmlNode primer = xmlDoc.DocumentElement;
exti = primer.Name;

First, to be clear, you're asking about the root element, not the root node.
You can use an XmlReader to avoid having to load large documents completely into memory. See my answer to a how to find the root element at https://stackoverflow.com/a/60642354/1307074.
Second, once the reader is referencing the element, you can use the reader's Name property to get the qualified tag name of the element. You can get the value as a string using the Value property.

Get certain xml node and save the value

Considering the following XML:
<Stations>
<Station>
<Code>HT</Code>
<Type>123</Type>
<Names>
<Short>H'bosch</Short>
<Middle>Den Bosch</Middle>
<Long>'s-Hertogenbosch</Long>
</Names>
<Country>NL</Country>
</Station>
</Stations>
There are multiple nodes. I need the value of each node.
I've got the XML from a webpage (http://webservices.ns.nl/ns-api-stations-v2)
Login (--) Pass (--)
Currently i take the XML as a string and parse it to a XDocument.
var xml = XDocument.Parse(xmlString);
foreach (var e in xml.Elements("Long"))
{
var stationName = e.ToString();
}

You can retrieve "Station" nodes using XPath, then get each subsequent child node using more XPath. This example isn't using Linq, which it looks like you possibly are trying to do from your question, but here it is:
XmlDocument xml = new XmlDocument();
xml.Load(xmlStream);
XmlNodeList stations = xml.SelectNodes("//Station");
foreach (XmlNode station in stations)
{
var code = station.SelectSingleNode("Code").InnerXml;
var type = station.SelectSingleNode("Type").InnerXml;
var longName = station.SelectSingleNode("Names/Long").InnerXml;
var blah = "you should get the point by now";
}
NOTE: If your xmlStream variable is a String, rather than a Stream, use xml.LoadXml(xmlStream); for line 2, instead of xml.Load(xmlStream). If this is the case, I would also encourage you to name your variable to be more accurately descriptive of the object you're working with (aka. xmlString).

This will give you all the values of "Long" for every Station element.
var xml = XDocument.Parse(xmlStream);
var longStationNames = xml.Elements("Long").Select(e => e.Value);