Linq to XML query creating empty items from XML
Can somebo开发者_开发知识库dy explain why is this xml
<?xml version="1.0" encoding="utf-8"?>
<items>
<item id="77" cityID="EE12345" cityDatum="15.2.2010. 11:28:35" />
</items>
when using query
Dim c = From items In st.Descendants _
Where items.@id IsNot Nothing _
Select New myStorage With {.id = items.@id, .cityID = items.@cityID, .cityDatum = items.@cityDatum}
storage = c.ToList
resulting in list(of myStorage) with two items - one with all empty (nothing) properties, second with values seen in xml above?
I've resolved the issue by adding
Where items.@id IsNot Nothing _
before Seletct New myStorage, but I have a feeling that I shouldn't be doing that.
I've recreated this in C#, storage.xml is exactly the same as specified above.
private void Form1_Load(object sender, EventArgs e)
{
XDocument st;
st = XDocument.Load("C:\\storage.xml");
Object c = from items in st.Descendants()
select new {id = items.Attribute("id"), cityID = items.Attribute("cityID"), cityDatum = items.Attribute("cityDatum")};
}
If you, as some can't replicate these results, here's a screenshot:
screenshot http://www.incito.hr/15.2.2010.png
Got it from your updated code sample. When you say
st = XDocument.Load("C:\\storage.xml");
and then
st.Descendants()
your st
is the document, not the root element. So when you ask it for its Descendants
, you enumerate over 2 XElement
s - the items
node and the one item
node that this example have. It is the items
node that is giving you the 'empty' item.
There are numerous ways to restrict yourself to just the item
nodes, depending on how sure you can be about the structure of your xml - for example,
From item In st.Root.Elements("item")
will enumerate over just the item
nodes found as immediate children of the document's root element.
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