I'm trying to add all the nodes in an XML file into a listView, and I'm doing something wrong but I can't for the life of me figure it out even after looking at a load of examples. This is the XML snippet:
<queue>
<slots>
<slot>
<status>Downloading</status>
<filename>file1</filename>
<size>1 GB</size>
</slot>
<slot>
<status>Downloading</status>
<filename>file2</filename>
<size>2 GB</size>
</slot>
</slots>
</queue>
And here's the code:
XDocument xDoc = XDocument.Load(xmlFilePath);
List<Download> list = new List<Download>();
foreach (var download in xDoc.Descendants("slots"))
{
string filename = download.Element("filename").Value;
string size = download.Element("size").Value;
string status = download.Element("status").Value;
list.Add(new Download { Filename = filename, Size = size, Status = status });
}
Any help greatly appreciated as always.
EDIT: To clarify, I'm getting a NullReferenceException on
string filename = download.Element("filename").Value;
And i know the listview is missing, I've not done that bit yet :)
var list = (from download in xDoc.Descendats("slot")
select new Download
{
Filename = (string) download.Element("filename"),
Size = (string) download.Element("size"),
Status = (string) download.Element("status")
}).ToList();
This looks nicer, and since you didn't say what exactly is wrong with your code, it's about all I can do.
Update: just tested this, and it fixes your exception.
The XML in your example works fine. The NullReferenceException is happening because the real XML you're using doesn't have a filename element in one of the slots. You can use
string filename = download.Element("filename") == null ?
String.Empty : download.Element("filename").Value;
instead if there is a possible default for the filename. But more likely correctly handling this exception is better.
void LoadSlots()
{
XmlDocument doc = new XmlDocument();
doc.Load(Environment.CurrentDirectory + "\\queue.xml");
XmlNodeList nodes = doc.SelectNodes("//queue/slots/slot");
foreach (XmlNode node in nodes)
{
string filename = node.Attributes["filename"].InnerText;
string size = node.Attributes["size"].InnerText;
string status = node.Attributes["status"].InnerText;
_slots.Add(filename, size, status);
}
}
Related
I am trying to figure out the code to extract xml child (I think this is worded correctly) elements. I have searched and tried many samples but cannot find how to drill down to pick out the section I want and return the information I need. Maybe I all I need is someone to define the data I am trying to pull so I can read up on the issue, of course any code would be very helpful and I will figure it out from there. Thanks in advanced for any help!
Here is the xml file. I am trying to run an if statement to find the section named <STATISTICTYPE>PVCAP_CharactersSaved</STATISTICTYPE> and return the <JOBNAME>,<TIMEDELTA>,<VALUESUM>.
<?xml version="1.0" encoding="utf-8"?>
<PVCAPTURESTATISTICCONTAINTER xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<PVCAPTUREJOBSTATISTICS>
<PVCAPTURESTATISTICSUMMARY>
<STATISTICTYPE>PVCAP_CharactersSaved</STATISTICTYPE>
<STATISTICNAME>Characters saved</STATISTICNAME>
<JOBID>24</JOBID>
<JOBNAME>HEAT FILES</JOBNAME>
<TIMEDELTA>422</TIMEDELTA>
<VALUESUM>25432</VALUESUM>
</PVCAPTURESTATISTICSUMMARY>
<PVCAPTURESTATISTICSUMMARY>
<STATISTICTYPE>PVCAP_CharactersSaved_NoMM</STATISTICTYPE>
<STATISTICNAME>Characters saved (no match and merge)</STATISTICNAME>
<JOBID>24</JOBID>
<JOBNAME>HEAT FILES</JOBNAME>
<TIMEDELTA>422</TIMEDELTA>
<VALUESUM>25432</VALUESUM>
</PVCAPTURESTATISTICSUMMARY>
</PVCAPTUREJOBSTATISTICS>
<DOCUMENTCOUNT>762</DOCUMENTCOUNT>
<PAGECOUNT>3194</PAGECOUNT>
<IMAGECOUNT>3194</IMAGECOUNT>
<VERSION>2.0</VERSION>
</PVCAPTURESTATISTICCONTAINTER>
You can use LINQ to XML, particularly the XElement class.
var element = XElement.Parse(xmlStr).Element("PVCAPTUREJOBSTATISTICS")
.Elements("PVCAPTURESTATISTICSUMMARY")
.First(c => c.Element("STATISTICTYPE").Value == "PVCAP_CharactersSaved")
var jobName = element.Element("JOBNAME").Value;
var timeDelta = element.Element("TIMEDELTA").Value;
var valueSum = element.Element("VALUESUM").Value;
You'll want to add in some error handling and whatnot here, but this should get you going in the right direction.
You can do something like this:
XElement res = XElement.Parse(xmlResult);
foreach(var elem in res.Element("PVCAPTUREJOBSTATISTICS").Elements("PVCAPTURESTATISTICSUMMARY"))
{
if (elem.Element("STATISTICTYPE").Value.Equals("PVCAP_CharactersSaved", StringComparison.Ordinal))
{
string jobName = elem.Element("JOBNAME").Value;
string timeDelta = elem.Element("TIMEDELTA").Value;
string valueSum = elem.Element("VALUESUM").Value;
}
}
You can use XDocument and LINQ-to-XML to do that quite easily, for example :
string xml = "your xml content here";
XDocument doc = XDocument.Parse(xml);
//or if you have the xml file instead :
//XDocument doc = XDocument.Load("path_to_xml_file.xml");
var result = doc.Descendants("PVCAPTURESTATISTICSUMMARY")
.Where(o => (string) o.Element("STATISTICTYPE") == "PVCAP_CharactersSaved")
.Select(o => new
{
jobname = (string) o.Element("JOBNAME"),
timedelta = (string) o.Element("TIMEDELTA"),
valuesum = (string) o.Element("VALUESUM")
});
foreach (var r in result)
{
Console.WriteLine(r);
}
I'm parsing a lot of XML files using Linq to XML synatx, everything works when I try to access top level elements
var indexroot = (from element in prodcutDocument.Root.Descendants("indexroot")
select new
{
model = (string)element.Element("MODEL"),
}).FirstOrDefault()
The problem occurs when I need to access lower level childs of that document I tried:
var indexroot = (from element in prodcutDocument.Root.Descendants("indexroot")
select new
{
ddName = (string)element.Descendants("DD_NAME").Elements("name").First();
}).FirstOrDefault()
and
var indexroot = (from element in prodcutDocument.Root.Descendants("indexroot").Descendants("DD_NAME")
select new
{
ddName = (string)element.Element("name")
}).FirstOrDefault();
Sadly none of that works and i get same error "Sequence contains no elements". And one more thing sometimes the XML document contains those tags and sometimes not is something like this enough for handling this case?
var indexroot = (from element in prodcutDocument.Root.Descendants("indexroot").Descendants("DD_NAME")
select new
{
ddName = (string)element.Element("name") ?? "-"
}).FirstOrDefault();
Edit:
I don't think is possible to paste short version of XML that would be simple, so here's full version: http://pastebin.com/uDkP3rnR and for the code example:
XDocument prodcutDocument = XDocument.Load(this.ServerPATHData + file);
var indexroot = (from element in prodcutDocument.Root.Descendants("indexroot")
select new
{
modelis = (string)element.Element("MODELIS"),
T2918_0 = (string)element.Descendants("dd_DARBINIS_GRAFIKAS_SPEC").First()
}).FirstOrDefault();
writeTxt.WriteLine("modelis: " + indexroot.modelis);
writeTxt.WriteLine("T2979_0" + indexroot.T2918_0);
In examining the sample XML that you posted on PasteBin, it appears to me that the elements that you mention appear only once. To access them, you can simply specify a path to each as follows:
XElement indexroot = document.Root.Element("indexroot");
XElement modelis = indexroot.Element("MODELIS");
XElement dd_dgs = indexroot.Element("dd_DARBINIS_GRAFIKAS_SPEC");
XElement voltageuv = dd_dgs.Element("VoltageUV");
string t2979_0 = (string)voltageuv.Element("T2979_0");
string t2861_60 = (string)voltageuv.Element("T2861_60");
string t2757_121 = (string)voltageuv.Element("T2757_121");
(Note that you may need to check for null if there is a chance that any of the elements you are trying to access may not be present. Without doing so, you'll encounter a NullReferenceException.)
Here is a snippet of the XML that you posted to give context to the above code:
<?xml version='1.0' encoding='UTF-8' standalone='no'?>
<PDB>
<indexroot>
<ed_BENDRA_MAKS_SUV_GALIA>1.45</ed_BENDRA_MAKS_SUV_GALIA>
<ed_BENDRA_MAKS_SROVE>6.48</ed_BENDRA_MAKS_SROVE>
<TIPAS>1</TIPAS>
<MODELIS>RIS 2500 HW EC 3.0</MODELIS>
<dd_DARBINIS_GRAFIKAS_SPEC>
<VoltageUV>
<T2979_0>229,42</T2979_0>
<T2861_60>227,98</T2861_60>
<T2757_121>228,97</T2757_121>
</VoltageUV>
<CurrentIA>
<T2979_0>2,56</T2979_0>
<T2861_60>2,63</T2861_60>
<T2757_121>2,72</T2757_121>
</CurrentIA>
</dd_DARBINIS_GRAFIKAS_SPEC>
</indexroot>
</PDB>
You can just change:
element.Descendants("dd_DARBINIS_GRAFIKAS_SPEC").First()
to this:
element.Descendants("dd_DARBINIS_GRAFIKAS_SPEC").FirstOrDefault() ?? "-"
everyone!
I have an XML file and need to change the value of a node, specifically the indicated line. The problem i have is that as you can see, there are many nodes.
How can i change this line? This XML file could be much larger, so i am looking for a solution that would take different amounts of 'launch.file' nodes into account.
The node that will need to be set to True will be identified by the corresponding NAME tag. So if i typed in ULTII, the DISABLED node for that block will be set to True. If i typed in Catl, then the DISABLED node for that block would be changed.
<?xml version="1.0" encoding="windows-1252"?>
<SBase.Doc Type="Launch" version="1,0">
<Descr>Launch</Descr>
<Filename>run.xml</Filename>
<Disabled>False</Disabled>
<Launch.ManualLoad>False</Launch.ManualLoad>
<Launch.File>
<Name>Catl</Name>
<Disabled>False</Disabled>
<ManualLoad>False</ManualLoad>
<Path>ft\catl\catl.exe</Path>
</Launch.File>
<Launch.File>
<Disabled>False</Disabled> <!-- change to True -->
<ManualLoad>False</ManualLoad>
<Name>ULTII</Name>
<Path>F:\ULTII.exe</Path>
<NewConsole>True</NewConsole>
</Launch.File>
<Launch.File>
<Name>ECA</Name>
<Disabled>False</Disabled>
<Path>C:\ECA.exe</Path>
</Launch.File>
</SBase.Doc>
I am using Visual Studio 2012, should you need to know.
Thank you to anyone who can help me out on this, i really appreciate it.
Heres my method to do what you want
private void DisableLaunchFile(string xmlfile, string launchFileName){
XDocument doc = XDocument.Load(xmlfile);
var launchFileElement = doc.Descendants("Launch.File").Where (d => d.Element("Name").Value == lauchFileName);
launchFileElement.Elements("Disabled").First().Value = true.ToString();
doc.Save(xmlfile);
}
Use it like:
string pathToXmlFile = //assign ;
DisableLaunchFile(pathToXmlFile, "Catl");
DisableLaunchFile(pathToXmlFile, "ULTII");
This can be achieved by using LINQ to XML (see XDocument Class).
Assuming that there is the single Launch.File element with Name element with value "ULTII":
var document = XDocument.Load(...);
var ultiiElement = document
.Descendants("Launch.File")
.Single(fileElement => fileElement.Element("Name").Value == "ULTII");
ultiiElement.Element("Disabled").Value = "True"; // or true.ToString()
document.Save(...);
This method will do the trick:
public void ChangeNode(string name, string filePath)
{
XDocument xDocument;
using (var streamReader = new StreamReader(filePath))
{
xDocument = XDocument.Parse(streamReader.ReadToEnd());
}
var nodes = xDocument.Descendants("Launch.File");
foreach (var node in nodes)
{
var nameNode = node.Descendants("Name").FirstOrDefault();
if (nameNode != null && nameNode.Value == name)
{
var disabledNode = node.Descendants("Disabled").FirstOrDefault();
if (disabledNode != null)
{
disabledNode.SetValue("True");
}
}
}
using (var streamWriter = new StreamWriter(filePath))
{
xDocument.Save(streamWriter);
}
}
The name you want to pass in is the name of the node that you want to change and the path is the file path to the xml file. So you might call it like:
ChangeNode("ULTII", "C:\\output.xml");
You may need to tidy this up a bit like matching the node name invariant of case or culture but it should get you started.
Hey all i have looked thoroughly through all the questions containing XDocument and while they are all giving an answer to what I'm looking for (mostly namespaces issues) it seems it just won't work for me.
The problem I'm having is that I'm unable to select any value, be it an attribute or element.
Using this XML
I'm trying to retrieve the speaker's fullname.
public void GetEvent()
{
var xdocument = XDocument.Load(#"Shared\techdays2013.xml");
XNamespace xmlns = "http://www.w3.org/2001/XMLSchema-instance";
var data = from c in xdocument.Descendants(xmlns + "speaker")
select c.Element(xmlns + "fullname").Value;
}
You can omit the namespace declaration in your linq statement.
public void GetEvent()
{
var xdocument = XDocument.Load(#"Shared\techdays2013.xml");
//XNamespace xmlns = "http://www.w3.org/2001/XMLSchema-instance";
var data = from c in xdocument.Descendants("speaker")
select c.Element("fullname").Value;
}
You can omit WebClient because you have direct local access to a file. I'm just showing a way to process your file on my machine.
void Main()
{
string p = #"http://events.feed.comportal.be/agenda.aspx?event=TechDays&year=2013&speakerlist=c%7CExperts";
using (var client = new WebClient())
{
string str = client.DownloadString(p);
var xml = XDocument.Parse(str);
var result = xml.Descendants("speaker")
.Select(speaker => GetNameOrDefault(speaker));
//LinqPad specific call
result.Dump();
}
}
public static string GetNameOrDefault(XElement element)
{
var name = element.Element("fullname");
return name != null ? name.Value : "no name";
}
prints:
Bart De Smet
Daniel Pearson
Scott Schnoll
Ilse Van Criekinge
John Craddock
Corey Hynes
Bryon Surace
Jeff Prosise
1) You have to drop the namespace
2) You'll have to query more precisely. All your <speaker> elements inside <speakers> have a fullname but in the next section I spotted <speaker id="94" />
A simple fix (maybe not the best) :
//untested
var data = from c in xdocument.Root.Descendants("speakers").Descendants("speaker")
select c.Element("fullname").Value;
You may want to specify the path more precise:
xdocument.Element("details").Element("tracks").Element("speakers").
I’ve got a problem witch I’ve been trying to solve almost for a week now, but it seems that, unfortunately, I can’t manage it by myself.
Maybe somebody could help me.
I’ve got this type of source XML:
<data>
<para1>24499</para1>
<para2>32080148</para2>
<para4>20e500cc6008d0f8ab1fd108b220ca261f85edd9</para4>
<para6></para6>
<timetype>4</timetype>
<fkcontent>964342</fkcontent>
<season>0</season>
<fmstoken><![CDATA[7bca3c544ad64e526806fb5a6b845148]]></fmstoken>
<fmstoken_user>32010484</fmstoken_user>
<fmstoken_time>1283165972</fmstoken_time>
<fmstoken_renew><![CDATA[http://www.sky.com/logic/fmstoken.php?method=refresh]]></fmstoken_renew>
<adserverXML><![CDATA[http://www.sky.de/dummy.xml]]></adserverXML>
<playlist>
<videoinfo quality="0" name="DSL 1000">
<id>24499</id>
<noad>1</noad>
<productplacement>0</productplacement>
<filename>http://www.sky.com/video/1/V_53511_BB00_E81016_46324_16x9-lq-512x288-vp6-c0_bbb491b3ce64ef667340a21e2bfb3594.f4v</filename>
<title><![CDATA[Who will be the winner?]]></title>
</videoinfo>
<videoinfo quality="1" name="DSL 2000">
<id>24499</id>
<noad>1</noad>
<productplacement>0</productplacement>
<filename>http://www.sky.de/video/1/V_53513_BB00_E81016_46324_16x9-hq-512x288-vp6-c0_fa948bc5429cf28455779666cc59cf5e.f4v</filename>
<title><![CDATA[Who will be the winner?]]></title>
</videoinfo>
</playlist>
</data>
And here are parts of the code that let me get required tag content from xml page above:
private static string getTagContent(string source, string tag)
{
string fullTagBegin = "<" + tag + ">";
string fullTagEnd = "</" + tag + ">";
int indexBegin = source.IndexOf(fullTagBegin) + fullTagBegin.Length;
int indexEnd = source.IndexOf(fullTagEnd);
int indexLength = indexEnd - indexBegin;
if (indexBegin == -1 || indexEnd == -1)
return "UNKNOWN";
return source.Substring(indexBegin, indexLength);
}
public static void Start(String url)
{
try
{
String urlXML = url;
WebClient wClient = new WebClient();
string sourceXML = wClient.DownloadString(urlXML);
sourceXML = sourceXML.Replace("]]>", "");
sourceXML = sourceXML.Replace("<![CDATA[", "");
String para1 = getTagContent(sourceXML, "para1");
String para2 = getTagContent(sourceXML, "para2");
String para4 = getTagContent(sourceXML, "para4");
String timetype = getTagContent(sourceXML, "timetype");
String fkcontent = getTagContent(sourceXML, "fkcontent");
String season = getTagContent(sourceXML, "season");
String fmstoken = getTagContent(sourceXML, "fmstoken");
String fmstoken_user = getTagContent(sourceXML, "fmstoken_user");
String fmstoken_time = getTagContent(sourceXML, "fmstoken_time");
String fmstoken_renew = getTagContent(sourceXML, "fmstoken_renew");
String filename = getTagContent(sourceXML, "filename").Replace("http://", "");
String title = System.Text.RegularExpressions.Regex.Replace(getTagContent(sourceXML, "title"), #"[^a-zA-Z0-9]","_");
The problem is:
everything works fine except the fact, that there are two "filename" and "title" tags in the source xml, but I need to choose only second ones, those that are under this line:
<videoinfo quality="1" name="DSL 2000">,
and somehow skip/ignore first ones, those that are above previous line and right under this line:
<videoinfo quality="0" name="DSL 1000">
I can't figure out how to do that.
(My only guess is that maybe it has something to do with XPathNavigator, but I’m not sure if that’s a right guess, and anyway, I don’t really understand how to use it properly).
Edit: problem solved.
I want to thank everyone who replied for your suggestions.
Really appreciated!
This is really not the right way to go about working with XML in .Net.
You didn't mention which version of .Net you are developing for. Depending on the version look into using XmlDocument, XDocument / LINQ to XML.
MSDN on LINQ to XML
MSDN on XmlDocument
You should really load the XML into XMlDocument object and then edit it.
But if you prefer to use your existing code, this dirty code should do the trick.
int indexBegin = source.IndexOf(fullTagBegin) == source.LastIndexOf(fullTagBegin) ? source.IndexOf(fullTagBegin) + fullTagBegin.Length : source.LastIndexOf(fullTagBegin) + fullTagBegin.Length;
int indexEnd = source.IndexOf(fullTagEnd) == source.LastIndexOf(fullTagEnd) ? source.IndexOf(fullTagEnd) : source.LastIndexOf(fullTagEnd);
This will move the indexes to the last occurrence of whatever tag you're looking for. Just replace your declarations with this ones.
Edit: Additionally, you use this easy few lines to find/manipulate your XML in a much cleaner way.
XmlDocument doc = new XmlDocument();
doc.Load(filename);
// or doc.LoadXML(fullXMLcode);
var elements = doc.GetElementsByTagName("title");
var element = elements.Item(elements.Count - 1); // returns the last element
// element.InnerText gets the value you need. You can use this property to change it, too
Hope this helps.
You need this XPath expression:
/data/playlist/videoinfo[2]/filename | /data/playlist/videoinfo[2]/title
Or
/data/playlist/videoinfo[2]/*[self::filename or self::title]
These expression return a node set with filename and title element in document order.
In C# (I'm not an expert):
XPathDocument doc = new XPathDocument("document.xml");
XPathNodeIterator nodeset = doc.CreateNavigator()
.Select("/data/playlist/videoinfo[2]/*[self::filename or self::title]");
foreach (XPathNavigator node in nodeset)
{
// Your code
}
As many people have already said, XPath and LINQ are both suitable. Here's LINQ to XML sample:
XDocument doc = XDocument.Load("yourXml.xml");
var result =
(from videoInfo in doc.Descendants("videoinfo")
let quality = videoInfo.Attribute("quality")
let name = videoInfo.Attribute("name")
where (quality != null && quality.Value == "1")
&& (name != null && name.Value == "DSL 2000")
select new
{
Title = videoInfo.Element("title"),
FileName = videoInfo.Element("filename")
}
).First();
string title = result.Title.Value;
string fileName = result.FileName.Value;