public static void AddFilter(this VistaFileDialog vfd, string extension)
{
if (!extension.StartsWith("."))
{
extension = "." + extension;
}
using (RegistryKey hkExt = Registry.ClassesRoot.OpenSubKey(extension))
{
if (hkExt == null || !(hkExt.GetValue(null) is string identifier))
{
return;
}
using (RegistryKey hkIdentifier = Registry.ClassesRoot.OpenSubKey(identifier))
{
if (hkIdentifier == null || !(hkIdentifier.GetValue(null) is string displayName))
{
return;
}
vfd.AddFilter(displayName, $"*{extension}");
}
}
}
public VistaFileDialogEvents(VistaFileDialog dialog)
{
if (dialog == null)
{
throw new ArgumentNullException("dialog");
}
_dialog = dialog;
}
public static void AddFilter(this VistaFileDialog vfd, string displayName, string pattern)
{
string filter = $@"{displayName}|{pattern}";
if (string.IsNullOrEmpty(vfd.Filter))
{
vfd.Filter = filter;
}
else
{
vfd.Filter += $@"|{filter}";
}
}
private static void TranslateDefaultExt([NotNull] VistaFileDialog dialog)
{
if (string.IsNullOrWhiteSpace(dialog.DefaultExt))
{
return;
}
var ext = "*." + dialog.DefaultExt;
var filter = dialog.Filter;
var filters = filter.Split('|');
for (var i = 1; i < filters.Length; i += 2)
{
if (filters[i] == ext)
{
dialog.FilterIndex = 1 + (i - 1) / 2;
}
}
}
