private async void WebView_ScriptNotify(object sender, NotifyEventArgs e)
{
string[] urlParts = e.Value.Split('?');
string docLocation = urlParts[0];
Uri docUri = new Uri("ms-appx:///" + docLocation);
var file = await Windows.Storage.StorageFile.GetFileFromApplicationUriAsync(docUri);
var props = await file.GetBasicPropertiesAsync();
var fileSize = props.Size;
string range = urlParts[1];
string[] rangeParts = range.Split('&');
string originalRangeStart = rangeParts[0];
ulong rangeStart;
// if the range start is negative then read from the end of the file
if (originalRangeStart.StartsWith("-"))
{
ulong rangeStartPositive = (ulong)Math.Abs(Convert.ToInt64(originalRangeStart));
rangeStart = fileSize - rangeStartPositive;
}
else
{
rangeStart = Convert.ToUInt64(originalRangeStart);
}
// if the end range is not specified then it goes to the end of the file
ulong rangeEnd = (rangeParts[1].Length == 0) ? fileSize : Convert.ToUInt64(rangeParts[1]);
var stream = await file.OpenReadAsync();
stream.Seek(rangeStart);
// get the number of bytes to read
uint count = (uint)(rangeEnd - rangeStart);
var bytes = new byte[count];
using (var dataReader = new DataReader(stream))
{
await dataReader.LoadAsync(count);
dataReader.ReadBytes(bytes);
}
string successFunction = string.Format("setTimeout(function() {{ window.CoreControls.PartRetrievers.WinRTPartRetriever.partSuccess('{0}', '{1}'); }}, 0);", Convert.ToBase64String(bytes), originalRangeStart);
MyWebView.InvokeScript("eval", new string[] { successFunction });
}
