How to Expression.Invoke an arbitrary LINQ 2 SQL Query

Posted by Remus Rusanu on Stack Overflow See other posts from Stack Overflow or by Remus Rusanu
Published on 2010-04-14T17:35:04Z Indexed on 2010/04/14 18:53 UTC
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Filed under:

c#

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LINQ

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linq-to-sql

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.NET

Say I take an arbitrary LINQ2SQL query's Expression, is it possible to invoke it somehow?

MyContext ctx1 = new MyContext("...");
var q = from t in ctx1.table1 where t.id = 1 select t;
Expression qe = q.Expression;
var res = Expression.Invoke(qe);

This throws ArgumentException "Expression of type System.Linq.IQueryable`1[...]' cannot be invoked".

My ultimate goal is to evaluate the same query on several different data contexts.

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