PredicateBuilder cannot convert to IQueryable?

Question

i has the function:

private IEnumerable<Promotion> MatchesKeyword(IEnumerable<Promotion> list, String keyword)
{
   ...snip...
}

which now executes the LINQ query:

private IEnumerable<Promotion> MatchesKeyword(IEnumerable<Promotion> list, String keyword)
{
   return list.Where(item => item.Name.ContainsText(keyword)
      || item.Description.ContainsText(keyword)
      ...snip...
   );
}

This code works quite well.

But I need to convert it to use PredicateBuilder:

private IEnumerable<Promotion> MatchesKeyword(IEnumerable<Promotion> list, String keyword)
{
   var predicate = PredicateBuilder.False<Promotion>();     

   predicate = predicate.Or(item => item.Name.ContainsText(keyword)
         || item.Description.ContainsText(keyword)
         ...snip...
   );

   return list.Where(predicate);
}

Which, oddly enough, does not compile. Line of failure:

return list.Where(predicate);

You can choose the errors:

• Instance argument: cannot convert from 'System.Collections.Generic.IEnumerable' to 'System.Linq.IQueryable'
• 'System.Collections.Generic.IEnumerable' does not contain a definition for “Where” and the best method of extension overloading. "System.Linq.Enumerable.Where (System.Collections.Generic.IEnumerable, System.Func)" has some invalid arguments
• 2: 'System.Linq.Expressions.Expression > ' 'System.Func'

? IEnumerable , IEnumerable .

, PredicateBuilder, any .

---

, PredicateBuilder:

private IEnumerable<Promotion> MatchesKeyword(IEnumerable<Promotion> list, String keyword)
{
   var predicate = PredicateBuilder.False<Promotion>();     

   predicate = predicate.Or(item => item.Name.ContainsText(keyword)
         || item.Description.ContainsText(keyword)
         ...snip...
   );

   DateTime dt = TryStrToDate(keyword);
   if (dt)
       predicate = predicate.Or(item => item.PromotionDate == dt);

   return list.Where(predicate);
}

... , , , , .

Answer 1

PredicateBuilder IQueryable<T>, .

return list.AsQueryable().Where(predicate);

.