In the below XML example, there can be many ''Element'' entries. For each ''Element'' there can only ever be a single ''System'' entry but there can be many ''Device'' entries alongside that ''System'' entry within the same ''Element''.
I would like to know for each ''Element'', how do I construct a LINQ to XML query in C# that can select data as follows:
for each ''Element'' where ''System'' CONTAINS ''1A7'', return only those ''Device''-''InfoB''-''Settings''-''name'' values that also have a ''Device''-''InfoA''-''Core'' value of FALSE and then put those matching values into a List.
The LINQ has proved to be very difficult for me over the last week. I've not posted a code snippet as I think that none of the large number of code snippets that I've worked through (and failed with) would clarify this question more than the query outline above. I would hugely appreciate some help with this and I'm hoping that the above query is fairly straightforward to the LINQ to XML experts on here.
XML:
<?xml version="1.0" standalone="yes" ?>
<Base_TP>
<Element>
<System>
<id>341A7</id>
</System>
<Device>
<InfoA>
<id>12</id>
<Core>TRUE</Core>
</InfoA>
<InfoB>
<Settings>
<type>0</type>
<name>DeviceA</name>
</Settings>
</InfoB>
</Device>
<Device>
<InfoA>
<id>13</id>
<Core>FALSE</Core>
</InfoA>
<InfoB>
<Settings>
<type>0</type>
<name>DeviceB</name>
</Settings>
</InfoB>
</Device>
<Device>
<InfoA>
<id>14</id>
<Core>FALSE</Core>
</InfoA>
<InfoB>
<Settings>
<type>0</type>
<name>DeviceC</name>
</Settings>
</InfoB>
</Device>
</Element>
</Base_TP>
var doc = XDocument.Load("Input.xml");
var values = from e in doc.Root.Elements("Element")
where ((string)e.Element("System").Element("id")).Contains("1A7")
from d in e.Elements("Device")
where !(bool)d.Element("InfoA").Element("Core")
select (string)d.Element("InfoB").Element("Settings").Element("name");
Returns IEnumerable<string>
. Call ToString
on it to get List<string>
with materialized results.
XDocument xDoc = XDocument.Load("System.xml");
List<string> result = xDoc.Descendants("Element").Where(el => el.Element("System").Element("id").Value.Contains("1A7")).SelectMany(e => e.Descendants("Device").Where(d => d.Element("InfoA").Element("Core").Value.ToUpper() == "FALSE").Select(x => x.Element("InfoB").Element("Settings").Element("name").Value)).ToList();
I'm going to do this in visual basic because it has native support for xml in-line but the translation is pretty simple.
Dim elements = From e In xml...<Element>
Where e.<System>.<Id>.Value.Contains("1A7")
Select e
Dim deviceBs = (From e In elements
Where e.<Device>.<InfoA>.<Core>.Value = "FALSE"
Select e.<Device>.<InfoB>.<name>.Value).ToList
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