/// <summary>Gets the file content for the specified FileDescriptor index.</summary>
/// <param name="index">The index of the file content to retrieve.</param>
public static MemoryStream GetFileContent(this System.Windows.Forms.IDataObject data, int index)
{
// As this is indexed, "FileContent" is most likely null, so the COM IDataObject needs to be used
var comData = (System.Runtime.InteropServices.ComTypes.IDataObject)data;
var formatetc = new FORMATETC()
{
cfFormat = (short)DataFormats.GetFormat("FileContents").Id,
dwAspect = DVASPECT.DVASPECT_CONTENT,
lindex = index,
ptd = IntPtr.Zero,
tymed = TYMED.TYMED_ISTREAM | TYMED.TYMED_HGLOBAL
};
var medium = new STGMEDIUM();
comData.GetData(ref formatetc, out medium);
switch (medium.tymed)
{
case TYMED.TYMED_HGLOBAL:
return(data.GetFileContentFromHGlobal(medium));
case TYMED.TYMED_ISTREAM:
return(data.GetFileContentFromIStream(medium));
default:
throw new InvalidOperationException($"Cannot get FileContent for {medium.tymed} TYMED.");
}
}