private static int CreateEnumeratorFromKeyImpl(IntPtr thisPtr, IntPtr factory, IntPtr collectionKey, int collectionKeySize, out IntPtr fontFileEnumerator)
{
fontFileEnumerator = IntPtr.Zero;
try
{
IDWriteFontCollectionLoaderShadow shadow = ToShadow <IDWriteFontCollectionLoaderShadow>(thisPtr);
IDWriteFontCollectionLoader callback = (IDWriteFontCollectionLoader)shadow.Callback;
Debug.Assert(factory == shadow._factory.NativePointer);
IDWriteFontFileEnumerator enumerator = callback.CreateEnumeratorFromKey(shadow._factory, collectionKey, collectionKeySize);
fontFileEnumerator = IDWriteFontFileEnumeratorShadow.ToIntPtr(enumerator);
}
catch (Exception exception)
{
return((int)Result.GetResultFromException(exception));
}
return(Result.Ok.Code);
}
HRESULT IDWriteFontCollectionLoader.CreateEnumeratorFromKey(IDWriteFactory factory, IntPtr collectionKey, uint collectionKeySize, out IDWriteFontFileEnumerator fontFileEnumerator)
{
var func = EnumerableFunc;
if (func == null)
{
fontFileEnumerator = null;
ComError.SetError(nameof(EnumerableFunc) + " was not set.");
return(HRESULTS.DISP_E_EXCEPTION);
}
byte[] key;
if (collectionKey == IntPtr.Zero || collectionKeySize == 0)
{
key = null;
}
else
{
key = new byte[collectionKeySize];
Marshal.Copy(collectionKey, key, 0, (int)collectionKeySize);
}
var enumerable = func(factory, key);
if (enumerable == null)
{
fontFileEnumerator = null;
ComError.SetError(nameof(EnumerableFunc) + " returned nothing.");
return(HRESULTS.DISP_E_EXCEPTION);
}
var enumerator = enumerable.GetEnumerator();
if (enumerator == null)
{
fontFileEnumerator = null;
ComError.SetError(nameof(EnumerableFunc) + " returned a null enumerator.");
return(HRESULTS.DISP_E_EXCEPTION);
}
fontFileEnumerator = new FontFileEnumerator(factory, _loader, enumerator);
return(HRESULTS.S_OK);
}
/// <summary> /// Return a pointer to the unmanaged version of this callback. /// </summary> /// <param name="callback">The callback.</param> /// <returns>A pointer to a shadow c++ callback</returns> public static IntPtr ToIntPtr(IDWriteFontFileEnumerator callback) => ToCallbackPtr <IDWriteFontFileEnumerator>(callback);
