public class Filters {
    public int var1 = 1,
          var2 = 2,
          var3 = 3;
}

Filters filter1 = new Filters();

foreach (var prop in filter1.props) {
    Console.WriteLine(filter1[prop] + 3);
}

4
5
6

public class Filters
{
    public int var1 { get; set; } = 1;
    public int var2 { get; set; } = 2;
    public int var3 { get; set; } = 3;
}

static void Main(string[] args)
{
    Filters filter1 = new Filters();

    foreach (var prop in filter1.GetType().GetProperties())
    {
        Console.WriteLine("{0}={1}", prop.Name, (int)prop.GetValue(filter1, null) + filter1.GetType().GetProperties().Length);
    }

    Console.ReadKey();
}

4
5
6

public class Filter
{
    public IDictionary<string, object> Properties { get; } = new Dictionary<string, object>();
}

public class Filter
{
    public int Var1 { get; set; } = 1;
    public int Var2 { get; set; } = 2;
    public int Var3 { get; set; } = 3;
}

var filter = new Filter();
var filterType = filter.GetType();
var readableProperties = filterType.GetProperties().Where( p => p.GetGetMethod() != null );

foreach (var property in readableProperties)
{
    var value = (int)property.GetValue( filter );
    Console.WriteLine( $"{property.Name} =  {value + 3}" );
}

FieldInfo[] fields = typeof(GeneralFilters).GetFields();
        for (int i = 0; i < fields.Length; i++)
        {
            //MANIPULATE HERE
            BlankTemplate tempFilter = (BlankTemplate)fields[i].GetValue(filters);
            // Ignore this for now.       tempFilter.selectedItems;
        }

public class BlankTemplate
{
    public string[] selectedItems;
    public bool selectAll = false;
}

var fieldNames = Object.keys(filterObject);
for (var i = 0; i < fieldNames.length; i++) {
    doSomething( filterObject[fieldNames[i]] );
}