public bool ContainsGeoHash(GeoHash hash)
{
var hashStr = hash.GetGeoHashString();
return(Compare(_startValue, hashStr, StringComparison.Ordinal) <= 0 &&
Compare(_endValue, hashStr, StringComparison.Ordinal) > 0);
}
public static GeoHashQuery QueryForGeoHash(GeoHash geohash, int bits)
{
var hash = geohash.GetGeoHashString();
var precision = (int)Math.Ceiling((double)bits / Base32Utils.BitsPerBase32Char);
if (hash.Length < precision)
{
return(new GeoHashQuery(hash, hash + "~"));
}
hash = hash.Substring(0, precision);
var hashBase = hash.Substring(0, hash.Length - 1);
var lastValue = Base32Utils.Base32CharToValue(hash[hash.Length - 1]);
var significantBits = bits - hashBase.Length * Base32Utils.BitsPerBase32Char;
var unusedBits = Base32Utils.BitsPerBase32Char - significantBits;
// delete unused bits
var startValue = (lastValue >> unusedBits) << unusedBits;
var endValue = startValue + (1 << unusedBits);
var startHash = hashBase + Base32Utils.ValueToBase32Char(startValue);
var endHash = endValue > 31 ? hashBase + "~" : hashBase + Base32Utils.ValueToBase32Char(endValue);
return(new GeoHashQuery(startHash, endHash));
}