namespace AliLoginForm
{
    public class MyIECookie
    {

        //[DllImport("wininet.dll", CharSet = CharSet.Auto, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
        //static extern bool InternetGetCookieEx(string pchURL, string pchCookieName, StringBuilder pchCookieData, ref int pcchCookieData, int dwFlags, IntPtr lpReserved);
        
 
//取出Cookie，當登錄後才能取    
        public static string GetCookieString(string url)
        {
            // Determine the size of the cookie      
            uint datasize = 256;
            StringBuilder cookieData = new StringBuilder((int)datasize);
            if (!InternetGetCookieEx(url, null, cookieData, ref
 
 datasize, 0x00002000, IntPtr.Zero))
            {
                if (datasize < 0)
                    return null;
                // Allocate stringbuilder large enough to hold the cookie    
                cookieData = new StringBuilder((int)datasize);
                if (!InternetGetCookieEx(url, null
 
, cookieData, ref datasize, 0x00002000, IntPtr.Zero))
                    return null;
            }
            return cookieData.ToString();
        }

        [DllImport("wininet.dll", CharSet = CharSet.Auto, SetLastError = true)]
        static extern bool InternetGetCookieEx(string pchURL, string pchCookieName, StringBuilder pchCookieData, ref System.UInt32 pcchCookieData, int dwFlags, IntPtr lpReserved);
    }
}

使用 InternetGetCookieEx 獲取webbrowser中的 cookie 包含 httponly