How can I find out when a picture was actually taken in C# running on Vista?

Here’s as fast and clean as you can get it. By using FileStream, you can tell GDI+ not to load the whole image for verification. It runs over 10 × as fast on my machine.

//we init this once so that if the function is repeatedly called
//it isn't stressing the garbage man
private static Regex r = new Regex(":");

//retrieves the datetime WITHOUT loading the whole image
public static DateTime GetDateTakenFromImage(string path)
{
    using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read))
    using (Image myImage = Image.FromStream(fs, false, false))
    {
        PropertyItem propItem = myImage.GetPropertyItem(36867);
        string dateTaken = r.Replace(Encoding.UTF8.GetString(propItem.Value), "-", 2);
        return DateTime.Parse(dateTaken);
    }
}

And yes, the correct id is 36867, not 306.

The other Open Source projects below should take note of this. It is a huge performance hit when processing thousands of files.