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PredicateBuilder to create a list of where conditions

I have something like this:

class myClass {
  protected ICollection<Expression<Func<event_info, bool>>> _whereConditionsList = new List<Expression<Func<event_info, bool>>>();

  public void main() {
    _whereConditionsList.Add(ev => ev.createdby == 6);
    var query = from ev in dataConnection.event_info
                where ev.isdeleted == 0
                select ev;
    if (_whereConditionsList.Count() > 0) {
      var predicate = PredicateBuilder.True<event_info>();

      foreach (var whereCond in _whereConditionsList) {
        predicate = predicate.And(whereCond);
      }
      query = query.Where(predicate);
    }
  evInfo = query.ToList(); 
}

But it's having trouble with actually converting it into SQL code because it throws this error whenever it gets to query.ToList():

System.NotSupportedException: The LINQ expression node type 'Invoke' is not supported in LINQ to Entities.
 ...
 at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
 ...

What am I doing wrong in my approach?

Turns out had to do this: Combine Predicates in Linq-to-entities

Synopsis: query.AsExpandable().Where()

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