x 509 root cerificate verification

I want to make x509 certificate root verification as manually. I used BouncyCastle Library. I added namespaces below

using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Security.Cryptography;

using System.Security.Cryptography.X509Certificates;

using Org.BouncyCastle.Asn1;

using Org.BouncyCastle.Asn1.Utilities;

using Org.BouncyCastle.Asn1.X509;

using Org.BouncyCastle.Crypto;

using Org.BouncyCastle.Math;

using Org.BouncyCastle.Security;

using Org.BouncyCastle.Security.Certificates;

using Org.BouncyCastle.Utilities;

using Org.BouncyCastle.Utilities.Collections;

using Org.BouncyCastle.Utilities.Date;

using Org.BouncyCastle.Utilities.Encoders;

using Org.BouncyCastle.X509.Extension;

and I called method below开发者_JAVA百科

    public static bool CertificateIssuerControl(X509Certificate2 certificate2Control, X509Certificate2 IssuerCertificate)
    {


        string signName = X509SignatureUtilities.GetSignatureName(certificate2Control.SignatureAlgorithm);
        ISigner signature = SignerUtilities.GetSigner(signName);
        return true;
    }

and I take "The name 'X509SignatureUtilities' does not exist in the current context" error

How can I solve this error?

Thank you for any advice...

You are not in the right namespace. Include org/bouncycastle/jce/provider/X509SignatureUtil.java or wrap/prefix with

namespace Org.BouncyCastle.X509 {
...
}

and you should be fine.

Dw.