public IEnumerable <KeyValuePair <TKey, TRecord> > Backward()
{
foreach (var kv in Index.Backward())
{
TKey key = KeyTransformer.FromIData(kv.Key);
TRecord rec = RecordTransformer.FromIData(kv.Value);
yield return(new KeyValuePair <TKey, TRecord>(key, rec));
}
}
public IEnumerable <KeyValuePair <TKey, TRecord> > Backward(TKey to, bool hasTo, TKey from, bool hasFrom)
{
IData ito = hasTo ? KeyTransformer.ToIData(to) : null;
IData ifrom = hasFrom ? KeyTransformer.ToIData(from) : null;
foreach (var kv in Index.Backward(ito, hasTo, ifrom, hasFrom))
{
TKey key = KeyTransformer.FromIData(kv.Key);
TRecord rec = RecordTransformer.FromIData(kv.Value);
yield return(new KeyValuePair <TKey, TRecord>(key, rec));
}
}
public KeyValuePair <TKey, TRecord>?FindBefore(TKey key)
{
IData ikey = KeyTransformer.ToIData(key);
KeyValuePair <IData, IData>?kv = Index.FindBefore(ikey);
if (!kv.HasValue)
{
return(null);
}
TKey k = KeyTransformer.FromIData(kv.Value.Key);
TRecord r = RecordTransformer.FromIData(kv.Value.Value);
return(new KeyValuePair <TKey, TRecord>(k, r));
}