public int IndexOf (X509Extension extension)
    {
        if (extension == null)
            throw new ArgumentNullException ("extension");

        for (int i=0; i < InnerList.Count; i++)
        {
            X509Extension ex = (X509Extension) InnerList [i];
            if (ex.Equals (extension))
                return i;
        }
        return -1;
    }
 public int IndexOf(X509Extension extension)
 {
     if (extension == null)
     {
         throw new ArgumentNullException("extension");
     }
     for (int i = 0; i < base.InnerList.Count; i++)
     {
         X509Extension x509Extension = (X509Extension)base.InnerList[i];
         if (x509Extension.Equals(extension))
         {
             return(i);
         }
     }
     return(-1);
 }