private async Task <byte[]> GetBitmapImpl(Geometry.MapTile tile)
{
try
{
string url = string.Format(_urlTemplate, tile.Zoom, tile.XNumber, tile.YNumber);
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
byte[] buffer = new byte[1024];
List <byte> outResult = new List <byte>();
using (HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync())
using (Stream responseStream = response.GetResponseStream())
{
int bytesRead = 0;
do
{
bytesRead = responseStream.Read(buffer, 0, buffer.Length);
outResult.AddRange(buffer.Take(bytesRead));
}while (bytesRead > 0);
}
return(outResult.ToArray());
}
catch (WebException)
{
return(null);
}
}
public async System.Threading.Tasks.Task <TBitmap> GetTileBitmap(Geometry.MapTile tile)
{
return(await _cache.GetItem(tile)); //System.Threading.Tasks.Task.Run(() => _cache[tile]);
}
public override Task <byte[]> GetBitmap(Geometry.MapTile tile)
{
return(GetBitmapImpl(tile));
}
public abstract Task <TBitmap> GetBitmap(Geometry.MapTile tile);