Casting Linq to Dataset <anonymous type> results to a data type for processing

Question

While debugging the following:

Dim Query = From p In dtClientsPrior Group p By clientId = p.Field(Of Int32)("Client_ID") Into Count() Where Count > 1
For Each row As Object In Query
 Debug.Print(row.GetType.ToString)
Next

When execution is stopped on the debug print line and hovering the mouse over the row varible the following displays:

row clientId=57001224, count=2
  <anonymous type> clientId=57001224, count=2

My question is how-to cast the <anonymous type> clientId and count to a data type in the loop to process each clientId in the output? 

Or how-to add linq statements to the Dim query statement to get non-anonymous type results?

Answer 1

Define a named class that implements the correct public fields, and then perform the cast to it.

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Answer 2

Hi Yogi;

Pieter is correct you will need to implement a type you want to be returned from the query. I have modified your query to show how the query can return a Type IEnumerable(Of QueryResults).

Dim Query = From p In dtClientsPrior
            Group p By clientId = p.Field(Of Int32)("Client_ID") Into Count() 
            Where Count > 1
            Select New QueryResults With
            	{
            			.ClientID = clientId,
            			.Count = Count
            	}
            
Public Class QueryResults
    Public ClientID As Integer
    Public Count As Integer
End Class  

  

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Fernando (MCSD)

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Answer 3

I Agree with previous 2 replies, you have to Enumerate the result that came out from the datatable, I do that by :

Dim Query = From p In dtClientsPrior.AsEnumerable Group p By clientId = p.Field(Of Int32)("Client_ID") Into Count() Where Count > 1 Select p

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