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copied!<p>After a wide research and a lot of study of Expressions I could write a solution myself. It certainly can be improved, but exactly fits my requirements. Hopefully it can help someone else.</p> <pre><code>//Return all items from a IEnumerable(target) that has at least one matching Property(propertyName) //with its value contained in a IEnumerable(possibleValues) static IEnumerable GetFilteredList(IEnumerable target, string propertyName, IEnumerable searchValues) { //Get target's T var targetType = target.GetType().GetGenericArguments().FirstOrDefault(); if (targetType == null) throw new ArgumentException("Should be IEnumerable<T>", "target"); //Get searchValues's T var searchValuesType = searchValues.GetType().GetGenericArguments().FirstOrDefault(); if (searchValuesType == null) throw new ArgumentException("Should be IEnumerable<T>", "searchValues"); //Create a p parameter with the type T of the items in the -> target IEnumerable<T> var containsLambdaParameter = Expression.Parameter(targetType, "p"); //Create a property accessor using the property name -> p.#propertyName# var property = Expression.Property(containsLambdaParameter, targetType, propertyName); //Create a constant with the -> IEnumerable<T> searchValues var searchValuesAsConstant = Expression.Constant(searchValues, searchValues.GetType()); //Create a method call -> searchValues.Contains(p.Id) var containsBody = Expression.Call(typeof(Enumerable), "Contains", new[] { searchValuesType }, searchValuesAsConstant, property); //Create a lambda expression with the parameter p -> p => searchValues.Contains(p.Id) var containsLambda = Expression.Lambda(containsBody, containsLambdaParameter); //Create a constant with the -> IEnumerable<T> target var targetAsConstant = Expression.Constant(target, target.GetType()); //Where(p => searchValues.Contains(p.Id)) var whereBody = Expression.Call(typeof(Enumerable), "Where", new[] { targetType }, targetAsConstant, containsLambda); //target.Where(p => searchValues.Contains(p.Id)) var whereLambda = Expression.Lambda<Func<IEnumerable>>(whereBody).Compile(); return whereLambda.Invoke(); } </code></pre>

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