int IColumnProvider.GetItemData(ref ShellColumnId columnId, ref ShellColumnData columnData, object data)
{
Debug.WriteLine("[{0}] ColumnProviderBase.IColumnProvider.GetItemData, columnId.FormatId={1}, columnId.PropertyId={2}",
Id, columnId.FormatId, columnId.PropertyId);
if (!initialized)
{
throw new COMException("Initialize was not called");
}
if (!IsSupportedItem(ref columnData))
{
////VariantInit(pvarData); // must initialise out args as we return a success code.
return(HResults.False);
}
bool flushCache = columnData.Flags.HasFlag(ShellColumnDataOptions.UpdateItem);
var fileName = Path.GetFileName(columnData.File);
object info = null;
if (!flushCache)
{
// User of this interface (explorer.exe) are expected to ask
// all active item data per file.
info = FindInLastUsedCache(fileName);
}
if (info == null)
{
info = GetAndCacheFileInfo(fileName, columnData.File, flushCache);
}
////pvarData->bstrVal = (*pCachedInfo)[GetIndex(*pscid)].AllocSysString();
////pvarData->vt = VT_BSTR;
return(HResults.Ok);
}
private bool IsSupportedItem(ref ShellColumnData columnData)
{
// Check file mask and file extension.
return(!columnData.FileAttributes.HasFlag(GetFileAttributeMask()) &&
extensions.Contains(columnData.FileNameExtension.ToLowerInvariant()));
}
