public static IPin GetPin(this IBaseFilter filter, PinDirection dir, int num)
{
IPin[] pin = new IPin[1];
IEnumPins pinsEnum = null;
if (filter.EnumPins(out pinsEnum) == 0)
{
PinDirection pinDir;
int n;
while (pinsEnum.Next(1, pin, out n) == 0)
{
pin[0].QueryDirection(out pinDir);
if (pinDir == dir)
{
if (num == 0)
return pin[0];
num--;
}
Marshal.ReleaseComObject(pin[0]);
pin[0] = null;
}
}
return null;
}