ConvertTo(
ITypeDescriptorContext context,
System.Globalization.CultureInfo culture,
object value,
Type destinationType
)
{
Toolbox.EmitEvent(EventTrace.Event.WClientDRXConvertImageBegin);
if (context == null)
{
throw new ArgumentNullException("context");
}
if (!IsSupportedType(destinationType))
{
throw new NotSupportedException(SR.Get(SRID.Converter_ConvertToNotSupported));
}
//
// Check that we have a valid BitmapSource instance.
//
BitmapSource bitmapSource = (BitmapSource)value;
if (bitmapSource == null)
{
throw new ArgumentException(SR.Get(SRID.MustBeOfType, "value", "BitmapSource"));
}
//
// Get the current serialization manager.
//
PackageSerializationManager manager = (PackageSerializationManager)context.GetService(typeof(XpsSerializationManager));
//Get the image Uri if it has already been serialized
Uri imageUri = GetBitmapSourceFromImageTable(manager, bitmapSource);
//
// Get the current page image cache
//
Dictionary <int, Uri> currentPageImageTable = manager.ResourcePolicy.CurrentPageImageTable;
if (imageUri != null)
{
int uriHashCode = imageUri.GetHashCode();
if (!currentPageImageTable.ContainsKey(uriHashCode))
{
//
// Also, add a relationship for the current page to this image
// resource. This is needed to conform with Xps specification.
//
manager.AddRelationshipToCurrentPage(imageUri, XpsS0Markup.ResourceRelationshipName);
currentPageImageTable.Add(uriHashCode, imageUri);
}
}
else
{
//
// This image as never serialized before so we will do it now.
// Retrieve the image serialization service from the resource policy
//
IServiceProvider resourceServiceProvider = manager.ResourcePolicy;
XpsImageSerializationService imageService = (XpsImageSerializationService)resourceServiceProvider.GetService(typeof(XpsImageSerializationService));
if (imageService == null)
{
throw new XpsSerializationException(SR.Get(SRID.ReachSerialization_NoImageService));
}
//
// Obtain a valid encoder for the image.
//
BitmapEncoder encoder = imageService.GetEncoder(bitmapSource);
string imageMimeType = GetImageMimeType(encoder);
bool isSupportedMimeType = imageService.IsSupportedMimeType(bitmapSource);
//
// Acquire a writable stream from the serialization manager and encode
// and serialize the image into the stream.
//
XpsResourceStream resourceStream = manager.AcquireResourceStream(typeof(BitmapSource), imageMimeType);
bool bCopiedStream = false;
BitmapFrame bitmapFrame = bitmapSource as BitmapFrame;
if (isSupportedMimeType &&
bitmapFrame != null &&
bitmapFrame.Decoder != null
)
{
BitmapDecoder decoder = bitmapFrame.Decoder;
try
{
Uri sourceUri = new Uri(decoder.ToString());
Stream srcStream = MS.Internal.WpfWebRequestHelper.CreateRequestAndGetResponseStream(sourceUri);
CopyImageStream(srcStream, resourceStream.Stream);
srcStream.Close();
bCopiedStream = true;
}
catch (UriFormatException)
{
//the uri was not valid we will re-encode the image below
}
catch (WebException)
{
//Web Request failed we will re-encode the image below
}
}
if (!bCopiedStream)
{
Stream stream = new MemoryStream();
ReEncodeImage(bitmapSource, encoder, stream);
stream.Position = 0;
CopyImageStream(stream, resourceStream.Stream);
}
//
// Make sure to commit the resource stream by releasing it.
//
imageUri = resourceStream.Uri;
manager.ReleaseResourceStream(typeof(BitmapSource));
AddBitmapSourceToImageTables(manager, imageUri);
}
Toolbox.EmitEvent(EventTrace.Event.WClientDRXConvertImageEnd);
return(imageUri);
}
