ClaimsReportIsMDLFilter

   public class ClaimsReportIsMDLFilter : ISearchFilter<vSEARCH_ClaimsReport> 
    {
        public Expression<Func<vSEARCH_ClaimsReport, bool>> GetExpression(string valuesToProcess)
        {

            Expression<Func<vSEARCH_ClaimsReport, bool>> mdlIsTrue = item => item.IsMDL == true;
            Expression<Func<vSEARCH_ClaimsReport, bool>> mdlIsFalse = item => item.IsMDL == false;
            Expression<Func<vSEARCH_ClaimsReport, bool>> mdlIsNull = item => item.IsMDL == null;

            var predicate = PredicateBuilder.False<vSEARCH_ClaimsReport>();

            if (string.IsNullOrWhiteSpace(valuesToProcess))
            {
                predicate = predicate
                    .Or(mdlIsTrue)
                    .Or(mdlIsFalse)
                    .Or(mdlIsNull);
            }
            else
            {
                if (!valuesToProcess.Contains("0") && !valuesToProcess.Contains("1"))
                {
                    throw new ArgumentException("Invalid IsMDL filter attribute specified");
                }
                if (valuesToProcess.Contains("0") && valuesToProcess.Contains("1"))
                {
                    predicate = predicate.Or(mdlIsTrue).Or(mdlIsFalse);
                }
                if (valuesToProcess.Contains("0"))
                {
                    predicate = predicate.Or(mdlIsFalse);
                }
                if (valuesToProcess.Contains("1"))
                {
                    predicate = predicate.Or(mdlIsTrue);
                }
            }


            return predicate;

        }
    }