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Dynamically insert Where and OrderBy clauses in Linq. How?

Hello.
I have this Lambda ExpressionSelect Code that works very well.

Dim listOfFiles = xdoc.Descendants("File") _
            .Select(Function(sfn) New With _
            { _
                .FileExtension = sfn.Attribute("Ext"), _
                .FileName = sfn.Attribute("FileName"), _
                .FileSize = sfn.Attribute("Size"), _
                .FolderAncestors = sfn.Ancestors("Folder").Aggregate("", Function(path As String, current As XElement) current.Attribute("FolderName").Value & "\" & path) _
            }).ToList()

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What if, depending on User's selection I would have to add a Where statement? For example Where FileName Like '%blue%'
Or more than one Where Statement, for example: Where FileName Like '%blue%' And FileExtension = '.doc'
How can I pass in such parameters and dynamically create such statement, no matter how many parameters?

Same thing with Order by - this time a User wants to Order By FileName Asc, and the other time by FolderAncestors Desc, FileExtension Asc.

Please help with examples.

Nasir Razzaq

See if this example helps

http://msdn.microsoft.com/en-us/library/bb882637.aspx

vituxa

ASKER

Can you please take my example and add a dynamic where and orderby to it?

Fernando Soto

Hi vituxa;

In your original XML file you do not have a "Ext" Attribute in the File node. Have you changed that so that File nodes do have Ext Attribute? If so can you please post new XML document so I can test the query.

vituxa

ASKER

Oh please don't worry about the ext. If you can give me the example of any other attribute - size, FileCreatedOn... Anything really.

Thank you Prodigy.

vituxa

ASKER

And is there a sign like in SQL you have a % sign, so I can query something like 'mico%sf' where % is being whatever is in the middle

ASKER CERTIFIED SOLUTION

Fernando Soto

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Fernando Soto

To your question, "And is there a sign like in SQL you have a % sign, so I can query something like 'mico%sf' where % is being whatever is in the middle", Well you do not have a sign but the Contains method translate to a SQL %. This can match in the beginning, middle or end. You can also use the methods StartsWith and EndsWith to match the beginning and the end of a string.

vituxa

ASKER

Thank you Prodigy!!! Once again saved me!

Fernando Soto

Not a problem vituxa, glad to be of help.