Convert Dataset to IQueryable<T> or IEnumerable<T>

linq datatable ienumerable iqueryable
jlembke picture jlembke · Feb 2, 2009 · Viewed 32.1k times · Source

Since there is no Linq to DB2 yet (c'mon IBM!), and I want to deal with IQueryables or IEnumerables in my code, how would I convert a DataTable to an IQueryable? Or an IEnumerable?

I have an interface and a class that matches the columns in the datatable...

IQueryable<IMyData> GetAS400Data(..parameters..)
{
    DataSet d = GetData();
    ...
    //Some code to convert d to IQueryable<IMyData>
}

DataTable.Rows does not support .AsQueryable, since MSFT yanked it, so I'm not sure what to do here.

Answer

Marc Gravell picture Marc Gravell · Feb 2, 2009 
table.AsEnumerable()...

table.AsEnumerable().AsQueryable()...

However, you'd need to write your own translation (Select) to your type; and the IQueryable<T> would still be using LINQ-to-Objects; the only purpose (in this scenario) of using IQueryable<T> over IEnumerable<T> would be to use expressions for some other reason - perhaps for the dynamic LINQ library.

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