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(FontFileEnumerator callback)
{
return(ToCallbackPtr <FontFileEnumerator>(callback));
}
/// <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(FontFileEnumerator callback)
{
return ToCallbackPtr<FontFileEnumerator>(callback);
}
