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Parsing xml string to get certain tag values within

I have an xml string and have different records within and i want to extract the id within each record. Here is a sample of the xml:
<UploadsInformation >
<Record>
<TaskGUID>48A583CA-A532-419A-9CDB-292764CEC541</TaskGUID>
</Record>
<Record>
<TaskGUID>ED6BA682-2BB2-4ADF-8355-9C605E16E088</TaskGUID>
</Record>
<Record>
<TaskGUID>D20D7042-FC5B-4CF7-9496-D2D9DB68CF52</TaskGUID>
</Record>
<Record>
<TaskGUID>F5DB10C5-D517-4CDA-8AAA-4E3F50B5FF3C</TaskGUID>
</Record>
</UploadsInformation>
This is what i have as a string to extract the information that i need but not sure if it correct or not because when i debug the string seems to be the xml file and not just the specified guid.
string data = new XDocument(new XElement("Record",
uploads.Select(guid => new XElement("TaskGUID", guid.ToString()))))
.ToString();
uploads is: List<Guid?> uploads

If I understand your question correctly, you want to extract the Guids from the source XML, which you indicate is a string.
You can create an XDocument from a string with the following command:
XDocument doc = XDocument.Parse(xmlString);
XNamespace ns = "http://schemas.acatar.com/2013/03/Malt.Models";
List<string> uploads = doc.Descendants(ns + "TaskGUID")
.Select(x => x.Value).ToList();
string uploadString = String.Join(",", uploads);
I used XNamespace because there is a namespace (two, actually) defined in the XML, and unless you prefix the correct one to the element name you won't get any results.
You might be able to combine the last two steps into one line, but I'm not 100% sure.
The above code was tested with your example, and produces the following value for uploadString:
48A583CA-A532-419A-9CDB-292764CEC541,ED6BA682-2BB2-4ADF-8355-9C605E16E088,D20D7042-FC5B-4CF7-9496-D2D9DB68CF52,F5DB10C5-D517-4CDA-8AAA-4E3F50B5FF3C
However, if you're going to loop through the result and pass each one in singularly to a stored procedure, I'd skip the String.Join and just loop through the List:
foreach (string id in uploads)
{
// Do your stored procedure call for each Guid.
}
Added in Response to Comment
In the situation in your comment, if you have a List that you want to get the values for, you'd do essentially the same, but you'll need to check for nulls and (probably) convert the Guid to a string before passing it into the stored proc:
foreach (Guid? g in uploads)
{
if (g != null)
{
string newGuid = g.ToString();
// do your data access stuff here
}
}

You can't use local names of elements, because you have namespace declared. So, you should use namespace to provide names:
XNamespace ns = "http://schemas.acatar.com/2013/03/Malt.Models";
var guids = from r in xdoc.Root.Elements(ns + "Record")
select Guid.Parse((string)r.Element(ns + "TaskGUID"));
Or query your xml without specifying names of elements:
var guids = xdoc.Root.Elements()
.Select(r => Guid.Parse((string)r.Elements().Single()));

I think this is either what you are after or perhaps might shed some light on the direction to go:
string xml = ""; // XML data here
XDocument doc = XDocument.Parse(xml);
List<Guid> guids = doc.Descendants("TaskGUID")
.Select(g => new Guid(g.Value))
.ToList();

C# - Issues Selecting XML with Linq

I am trying to pull an event description in XML, but I am having trouble accessing the data.
I am trying to access the eventDetailsValue element.
Here is a sample of my code:
(version 1)
XElement doc = XElement.Parse(e.Result);
evtDesc = doc.Element("eventDetails").Element("eventDetails").Element("eventDetailsValue").Element("eventDetailsValue").Value;
(version2)
XElement doc = XElement.Parse(e.Result);
var xGood = from detaildoc in doc.Descendants("eventDetails")
from d in detaildoc.Elements("eventDetail").Elements("eventDetailsValue")
select d;
I have tried the following for a different element and it worked:
GeoLat = Convert.ToDouble(doc.Element("latitude").Value);
Here is a sample of the xml result (i removed the values for simplicity):
<event>
<longitude></longitude>
<latitude></latitude>
<category></category>
<dma></dma>
<activeAdvantage></activeAdvantage>
<seoUrl></seoUrl>
<assetID></assetID>
<eventID></eventID>
<eventDetailsPageUrl></eventDetailsPageUrl>
- <mediaTypes>
<mediaType></mediaType>
<mediaType></mediaType>
<mediaType></mediaType>
<mediaType></mediaType>
<mediaType></mediaType>
</mediaTypes>
<eventContactEmail />
<eventContactPhone />
<eventName></eventName>
<eventDate></eventDate>
<eventLocation></eventLocation>
<eventAddress></eventAddress>
<eventCity></eventCity>
<eventState></eventState>
<eventZip></eventZip>
<eventCountry></eventCountry>
<usatSanctioned></usatSanctioned>
<regOnline></regOnline>
<eventCloseDate></eventCloseDate>
<currencyCode></currencyCode>
<eventTypeID></eventTypeID>
<eventType></eventType>
<hasEventResults></hasEventResults>
<hasMetaResults></hasMetaResults>
<showMap></showMap>
<eventContactEmail />
<eventContactPhone />
<displayCloseDate></displayCloseDate>
<excludedFromEmailing></excludedFromEmailing>
<regOpensMessage />
<regFunnel></regFunnel>
<isValid></isValid>
<displayRegistration></displayRegistration>
- <channels>
- <channel>
<channelName></channelName>
<primaryChannel></primaryChannel>
</channel>
</channels>
- <eventDetails>
- <eventDetail>
<eventDetailsName></eventDetailsName>
<eventDetailsOrder></eventDetailsOrder>
<eventDetailsValue></eventDetailsValue>
</eventDetail>
- <eventDetail>
<eventDetailsName></eventDetailsName>
<eventDetailsOrder></eventDetailsOrder>
<eventDetailsValue></eventDetailsValue>
</eventDetail>
</eventDetails>
<eventDonationLinks />
<eventSanctions />
- <eventCategories>
- <eventCategory>
<categoryID></categoryID>
<categoryGroupCount></categoryGroupCount>
<categoryName></categoryName>
<categoryType></categoryType>
<categoryOrder></categoryOrder>
<numRegistered></numRegistered>
<maxRegistrations></maxRegistrations>
<percentFull></percentFull>
<displayDate></displayDate>
<closeDate></closeDate>
<actualCloseDate></actualCloseDate>
<isExpired></isExpired>
- <priceChanges>
- <priceChange>
<price></price>
<priceUntilDate></priceUntilDate>
</priceChange>
</priceChanges>
</eventCategory>
</eventCategories>
<eventUrl></eventUrl>
<eventContactUrl></eventContactUrl>
<eventImageUrl></eventImageUrl>
</event>
Any help would be appreciated!

The eventDetailsValue is in an array of eventDetail elements. So you need to diferentiate which element in the array you want. With this (and these LinqToXml extensions: http://searisen.com/xmllib/extensions.wiki) you can write it like this:
XElement doc = XElement.Parse(e.Result);
var details = doc.GetEnumerable("eventDetails/eventDetail", x => new
{
Name = x.Get("eventDetailsName", string.Empty),
Order = x.Get("eventDetailsOrder", string.Empty),
Value = x.Get("eventDetailsValue", string.Empty)
});
details is an IEnumerable<object> of Name's, Order's and the Value(s) you want. You can now loop through details and get the value(s) you want. I made Name, Order and Value all be strings, but by calling Get<type>("name", defaultValueByType) you can have them be other types instead.
You can loop through them like this:
foreach(var detail in details)
{
string value = detail.Value;
}
GetEnumerable is shorthand (in this case) for:
doc.Element("eventDetails").Elements("eventDetail").Select(x => new ...)
But it does null checking for you, which if your xml always produces the above xml, there would be no problems to do it long hand. And Get returns the proper value.
Note: Because this is a WindowsPhone7 project, you'll have to set a compiler flag of WindowsPhone7 so that the extensions compile without complaint (hopefully/I haven't tested it).

Try this query:
var xGood = from detaildoc in doc.Descendants("eventDetails")
select new
{
Value = detaildoc.Elements("eventDetail").Elements("eventDetailsValue").Value
};

Load repetitively-named XML nodes using Linq [C#]

I'm working on a program that needs to be able to load object-properties from an XML file. These properties are configurable by the user and XML makes sense to me to use.
Take the following XML document.
<?xml version="1.0" encoding="utf-8" ?>
<udpcommands>
<command name="requser">
<cvar name="reqchallege" value="false" />
</command>
<command name="reqprocs">
<cvar name="reqchallenge" value="false" />
</command>
</udpcommands>
I need to be able to load values from the cvars above to properties. I'm think Linq-To-XML would be good for it (I'm looking for applications of Linq so I can learn it). I've got a Linq-to-XML query done to select the right "command" based on the name.I was reading MSDN for help on this.
The following code snippet goes in a constructor that takes the parameter "string name" which identifies the correct XML <command> to pull.
I would like to have one linq statement to pull each <cvar> out of that XML given the section name, dumping everything to an IEnumerable. Or, I'm looking for a better option perhaps. I'm open for anything really. I would just like to use Linq so I can learn it better.
XElement doc = XElement.Load("udpcommands.xml");
IEnumerable<XElement> a = from el in doc.Elements()
where el.FirstAttribute.Value == name
select el;
foreach (var c in a)
{
Console.WriteLine(c);
}
The above code snippet outputs the following to the console:
<command name="requser">
<cvar name="reqchallege" value="false" />
</command>

Something like this should do:
var result =
doc.Elements("command")
.Single( x => x.Attribute("name").Value == name)
.Elements("cvar");
This will give you an IEnumerable<XElement> where each XElement represents a cvar in the specified command.
Note that if the specified command does not exist, the call to Single will cause an error. Likewise if the specified attribute is not found on the command.
EDIT As per your comments, you could do something along the lines of:
// Result will be an XElement,
// or null if the command with the specified attribute is not found
var result =
doc.Elements("command")
// Note the extra condition below
.SingleOrDefault( x => x.Attribute("name")!=null && x.Attribute("name").Value == name)
if(result!=null)
{
// results.Elements() gives IEnumerable<XElement>
foreach(var cvar in results.Elements("cvar"))
{
var cvarName = cvar.Attribute("name").Value;
var cvarValue = Convert.ToBoolean( cvar.Attribute("value").Value );
}
}

How to save XML node back into XML file with LINQ-to-XML?

I've got an XML file which I use to create objects, change the objects, then save the objects back into the XML file.
What do I have to change in the following code so that it extracts a node from the XML based on the id, replaces that node with the new one, and saves it back into the XML?
The following gives me 'System.Xml.Linq.XElement' does not contain a constructor that takes '0' arguments':
//GET ALL SMARTFORMS AS XML
XDocument xmlDoc = null;
try
{
xmlDoc = XDocument.Load(FullXmlDataStorePathAndFileName);
}
catch (Exception ex)
{
HandleXmlFileNotFound(ex);
}
//EXTRACT THE NODE THAT NEEDS TO BE REPLACED
XElement oldElementToOverwrite = xmlDoc.Descendants("smartForm")
.Where(sf => (int)sf.Element("id") == 2)
.Select(sf => new XElement());
//CREATE THE NODE THAT WILL REPLACE IT
XElement newElementToSave = new XElement("smartForm",
new XElement("id", this.Id),
new XElement("idCode", this.IdCode),
new XElement("title", this.Title)
);
//OVERWRITE OLD WITH NEW
oldElementToOverwrite.ReplaceWith(newElementToSave);
//SAVE XML BACK TO FILE
xmlDoc.Save(FullXmlDataStorePathAndFileName);
XML file:
<?xml version="1.0" encoding="utf-8" ?>
<root>
<smartForm>
<id>1</id>
<whenCreated>2008-12-31</whenCreated>
<itemOwner>system</itemOwner>
<publishStatus>published</publishStatus>
<correctionOfId>0</correctionOfId>
<idCode>customerSpecial</idCode>
<title>Edit Customer Special</title>
<description>This form has a special setup.</description>
<labelWidth>200</labelWidth>
</smartForm>
<smartForm>
<id>2</id>
<whenCreated>2008-12-31</whenCreated>
<itemOwner>system</itemOwner>
<publishStatus>published</publishStatus>
<correctionOfId>0</correctionOfId>
<idCode>customersMain</idCode>
<title>Edit Customer</title>
<description>This form allows you to edit a customer.</description>
<labelWidth>100</labelWidth>
</smartForm>
<smartForm>
<id>3</id>
<whenCreated>2008-12-31</whenCreated>
<itemOwner>system</itemOwner>
<publishStatus>published</publishStatus>
<correctionOfId>0</correctionOfId>
<idCode>customersNameOnly</idCode>
<title>Edit Customer Name</title>
<description>This form allows you to edit a customer's name only.</description>
<labelWidth>100</labelWidth>
</smartForm>
</root>

Well, the error has nothing to do with saving, or even with replacement - it has to do with you trying to create an XElement without specifying the name. Why are you trying to use Select at all? My guess is you just want to use Single:
XElement oldElementToOverwrite = xmlDoc.Descendants("smartForm")
.Where(sf => (int)sf.Element("id") == 2)
.Single();
(As Noldorin notes, you can give Single a predicate to avoid using Where at all. Personally I quite like to split the two operations up, but they'll be semantically equivalent.)
That will return the single element in the sequence, or throw an exception if there are 0 elements or more than one. Alternatives are to use SingleOrDefault, First, or FirstOrDefault:
SingleOrDefault if it's legal to have 0 or 1
First if it's legal to have 1 or more
FirstOrDefault if it's legal to have 0 or more
If you're using an "OrDefault" one, the result will be null if there are no matches.

I think the problem is simply your use of the Select call in the statement assigning oldElementToOverwrite. You actually seem to want the Single extension method.
XElement oldElementToOverwrite = xmlDoc.Descendants("smartForm")
.Single(sf => (int)sf.Element("id") == 2)

Can I avoid having to use fully-qualified element names in LINQ to XML?

Say I call XElement.Parse() with the following XML string:
var xml = XElement.Parse(#"
<?xml version="1.0" encoding="UTF-8"?>
<AccessControlPolicy xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
<Owner>
<ID>7c75442509c41100b6a413b88b523bd6f46554cdbee5b6cbe27bc08cb3f6a865</ID>
<DisplayName>me</DisplayName>
</Owner>
<AccessControlList>
<Grant>
<Grantee xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="Group">
...
");
When it comes time to query the element, I'm forced to use fully-qualified element names because that XML document contains an xmlns attribute in its root. This requires cumbersome creations of XName instances:
var AWS_XMLNS = "http://s3.amazonaws.com/doc/2006-03-01/";
var ownerElement = xml.Element(XName.Get("AccessControlPolicy", AWS_XMLNS)).Element(XName.Get("Owner", AWS_XMLNS));
When what I really want is simply,
var ownerElement = xml.Element("AccessControlPolicy").Element("Owner");
Is there a way to make LINQ to XML assume a specific namespace so I don't have to keep specifying it?

You could simplify by using
XNamespace ns = "http://s3.amazonaws.com/doc/2006-03-01/";
var ownerElement = xml.Element(ns + "AccessControlPolicy").Element(ns + "Owner");

I don't think you can (see Jon Skeet's comment), but there are a few tricks you can do.
1) create an extension method that appends the XNamespace to your string
2) Use VB?!?