public static extern bool CryptEncodeObjectEx(
     CryptEncodingTypes dwCertEncodingType,
     IntPtr lpszStructType,
     IntPtr pvStructInfo,
     CryptEncodeObjectFlags dwFlags,
     IntPtr pEncodePara,
     IntPtr pvEncoded,
     ref uint pcbEncoded);
 public static extern bool CryptDecodeObjectEx(
     CryptEncodingTypes dwCertEncodingType,
     IntPtr lpszStructType,
     IntPtr pbEncoded,
     int cbEncoded,
     CryptDecodeObjectFlags dwFlags,
     IntPtr pDecodePara,
     IntPtr pvStructInfo,
     ref int pcbStructInfo);