01-ISieve.CS

    public interface ISieve<TTypeOfObjectToFilter>
    {
        ISieve<TTypeOfObjectToFilter, TPropertyType> ForProperty<TPropertyType>(Expression<Func<TTypeOfObjectToFilter, TPropertyType>> propertyExpression);
    }
    
/// <summary>
/// Every Sieve (EqualitySieve, LessThanSieve, GreaterThanSieve) should supply this functionality.
/// </summary>
/// <typeparam name="TTypeOfObjectToFilter"></typeparam>
/// <typeparam name="TPropertyType"></typeparam>
public interface ISieve<TTypeOfObjectToFilter, TPropertyType>
{
    InvalidValueBehavior InvalidValueBehavior { get; }
    EmptyValuesListBehavior EmptyValuesListBehavior { get; }
    IEnumerable<string> DefaultSeparators { get; }
    IEnumerable<string> Separators { get; }
    PropertyInfo PropertyToFilter { get; }
    Expression<Func<TTypeOfObjectToFilter, bool>> ToExpression();
    Func<TTypeOfObjectToFilter, bool> ToCompiledExpression();
    ICollection<TPropertyType> AcceptableValues { get; }

    ISieve<TTypeOfObjectToFilter, TPropertyType> ForProperty(Expression<Func<TTypeOfObjectToFilter, TPropertyType>> propertyExpression);

    ISieve<TTypeOfObjectToFilter, TPropertyType> ForValue(string stringValue);
    ISieve<TTypeOfObjectToFilter, TPropertyType> ForValue(TPropertyType acceptableValue);

    ISieve<TTypeOfObjectToFilter, TPropertyType> ForValues(IEnumerable<string> acceptableValues);
    ISieve<TTypeOfObjectToFilter, TPropertyType> ForValues(IEnumerable<TPropertyType> acceptableValues);
    ISieve<TTypeOfObjectToFilter, TPropertyType> ForValues(string valuesListToParse);

    ISieve<TTypeOfObjectToFilter, TPropertyType> ForAdditionalValue(string additionalValue);
    ISieve<TTypeOfObjectToFilter, TPropertyType> ForAdditionalValue(TPropertyType additionalValue);
    
    ISieve<TTypeOfObjectToFilter, TPropertyType> ForAdditionalValues(IEnumerable<string> acceptableValues);
    ISieve<TTypeOfObjectToFilter, TPropertyType> ForAdditionalValues(IEnumerable<TPropertyType> listOfValues);
    ISieve<TTypeOfObjectToFilter, TPropertyType> ForAdditionalValues(string listOfValues);
    
    ISieve<TTypeOfObjectToFilter, TPropertyType> WithSeparator(string newSeparatorString);
    ISieve<TTypeOfObjectToFilter, TPropertyType> WithSeparators(IEnumerable<string> separatorStrings);
    
    ISieve<TTypeOfObjectToFilter, TPropertyType> WithEmptyValuesListBehavior(EmptyValuesListBehavior emptyValuesListBehavior);
    ISieve<TTypeOfObjectToFilter, TPropertyType> WithInvalidValueBehavior(InvalidValueBehavior invalidValueBehavior);
}

02-IFindableSieve.cs

public interface IFindableSieve<TTypeOfObjectToFilter>
{
    ISieve<TTypeOfObjectToFilter> GetSieve();
}

03-Goal.cs

// The end goal is to be able to do something like this.
// This is entirely pseudo-code.

// The general idea -- be able to find all of the appropriate sieves for a given propery or name,
// and then pass in all the values those Sieves should accept.
// Then, the resulting sieves coudl be passed into something like an OR/M as expressions,
// and something like a SQL where statement could be constructed from them.

//obviously this would be designed better and built-in to Sieve .NET itself.

  var filterNamesAndValuesFromQueryString = new NameValueCollection
      {
          {"LastName", "Smith, Johnson, Jones"},
          {"FirstName", "Harry, Sally, Frank"}
      };
      
var keys = filterNamesAndValuesFromQueryString.GetAllKeys();

var sieves = new SieveLocator<Person>().GetSievesForProperties(keys); // returns instances of applicable sieves.

foreach(var keyItem in keys)
{
  var matchingSieves = sieves.Where(x=>x.PropertyToFilter.Name == keyItem);
  
  var result = new List<ISieve<Person>>();
  
  foreach (var sieveItem in matchingSieves)
  {
    result.Add(sieve.ForValues(filterNamesAndValuesFromQueryString[keyItem]).WithSeparator(","));
  }
  
}

// at this point, we'd use a predicate builder or something to "And" sieveItem.ToExpression() to the other Sieve items
// and create something that could be parsed by an OR/M.