Linq to List and IEnumerable issues
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by Otaku
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Published on 2009-09-19T19:23:34Z
Indexed on
2010/03/12
22:57 UTC
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I am querying an HTML file with Linq. It looks something like this:
<html>
<body>
<div class="Players">
<div class="role">Goalies</div>
<div class="name">John Smith</div>
<div class="name">Shawn Xie</div>
<div class="role">Right Wings</div>
<div class="name">Jack Davis</div>
<div class="name">Carl Yuns</div>
<div class="name">Wayne Gortonia</div>
<div class="role">Centers</div>
<div class="name">Lutz Gaspy</div>
<div class="name">John Jacobs</div>
</div
</html>
</body>
What I'm trying to do is create a list of these folks like in a list of a structure called Players:
Structure Players
Public Name As String
Public Position As String
End Structure
But I've quickly found out I don't really know what I'm doing when it comes to Linq.
I've got this far my my queries:
Dim goalieList = From d In player.Elements _
Where d.Value = "Goalies" _
Select From g In d.ElementsAfterSelf _
Take While (g.@class <> "role") _
Select New Players With {.Position = "Goalie", _
.Name = g.Value}
Dim centersList = From d In player.Elements _
Where d.Value = "Centers" _
Select From g In d.ElementsAfterSelf _
Take While (g.@class <> "role") _
Select New Players With {.Position = "Centers", _
.Name = g.Value}
Which gets me down to the the players by position, but then I can't do much with this afterwards the result type is System.Collections.Generic.IEnumerable(Of System.Collections.Generic.IEnumerable(Of Player))
What I want to do is add these two results to a new list, like:
Dim playersList As List(Of Players) = Nothing
playersList.AddRange(centersList)
playersList.AddRange(goalieList)
So that I can then query the list and use it. But it kicks the error:
Unable to cast object of type 'WhereSelectEnumerableIterator
2[System.Xml.Linq.XElement,System.Collections.Generic.IEnumerable1[Players]]' to type 'System.Collections.Generic.IEnumerable`1[Players]'
As you can see, I may really have no idea how to work with all these objects/classes. Does anyone have any insight on what I may be doing wrong and how I can resolve it?
RESOLVED: The Linq query needs to return a single iEnumerable, like this:
Dim goalieList = From l In _
(From d In players.Elements _
Where d.Value = "Goalies" _
Select d.ElementsAfterSelf.TakeWhile(Function(f) f.@class <> "role")) _
Select New Players With {.Position = "Goalie", .Name = l.Value}
and then use goalieList.ToList
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