Filter.cs

using System;
using System.Runtime.CompilerServices;

[assembly: InternalsVisibleTo("DataPipelineTools.Tests")]
namespace SqlCollaborative.Azure.DataPipelineTools.Common
{
    public class Filter<T>
    {
        public string PropertyName { get; set; }
        public Type PropertyType { get; set; }
        public string Operator { get; set; }
        public string Value { get; set; }
        public bool IsValid { get; set; } = false;
        public string ErrorMessage { get; set; } = null;

        public string GetDynamicLinqString()
        {
            switch (Operator)
            {
                case "like":
                    var RegexMatchFunc = $"{nameof(DynamicLinqUtils)}.{nameof(DynamicLinqUtils.IsRegexMatch)}";
                    return $"{RegexMatchFunc}({PropertyName}, @0)";
                default:
                    return $"{PropertyName} {Operator} @0";
            }
        }

        public object GetDynamicLinqValue()
        {
            // Avoid throwing trying to do an invalid cast
            if (!IsValid)
                return null;

            switch (PropertyType.Name)
            {
                case nameof(DateTime):
                    return DateTime.Parse(Value);
                case nameof(DateTimeOffset):
                    return DateTimeOffset.Parse(Value);
                default:
                    return Operator == "like" ? Value.Replace("*", ".*") : Value;
            }
        }


        #region Newtonsoft.Json serialization methods
        public bool ShouldSerializeIsValid() => false;
        public bool ShouldSerializePropertyType() => false;
        #endregion Newtonsoft.Json serialization methods
    }
}