internal static (X509Certificate2 certificate, X509Certificate2Collection) GenerateCertificates(string name, string?testName = null)
{
X509Certificate2Collection chain = new X509Certificate2Collection();
X509ExtensionCollection extensions = new X509ExtensionCollection();
SubjectAlternativeNameBuilder builder = new SubjectAlternativeNameBuilder();
builder.AddDnsName(name);
extensions.Add(builder.Build());
extensions.Add(s_eeConstraints);
extensions.Add(s_eeKeyUsage);
extensions.Add(s_tlsServerEku);
CertificateAuthority.BuildPrivatePki(
PkiOptions.IssuerRevocationViaCrl,
out RevocationResponder responder,
out CertificateAuthority root,
out CertificateAuthority intermediate,
out X509Certificate2 endEntity,
subjectName: name,
testName: testName,
keySize: 2048,
extensions: extensions);
chain.Add(intermediate.CloneIssuerCert());
chain.Add(root.CloneIssuerCert());
responder.Dispose();
root.Dispose();
intermediate.Dispose();
return(endEntity, chain);
}
internal static (X509Certificate2 certificate, X509Certificate2Collection) GenerateCertificates(string targetName, [CallerMemberName] string?testName = null, bool longChain = false, bool serverCertificate = true)
{
const int keySize = 2048;
if (PlatformDetection.IsWindows && testName != null)
{
CleanupCertificates(testName);
}
X509Certificate2Collection chain = new X509Certificate2Collection();
X509ExtensionCollection extensions = new X509ExtensionCollection();
SubjectAlternativeNameBuilder builder = new SubjectAlternativeNameBuilder();
builder.AddDnsName(targetName);
extensions.Add(builder.Build());
extensions.Add(s_eeConstraints);
extensions.Add(s_eeKeyUsage);
extensions.Add(serverCertificate ? s_tlsServerEku : s_tlsClientEku);
CertificateAuthority.BuildPrivatePki(
PkiOptions.IssuerRevocationViaCrl,
out RevocationResponder responder,
out CertificateAuthority root,
out CertificateAuthority[] intermediates,
private static X509ExtensionCollection BuildTlsCertExtensions(string targetName, bool serverCertificate)
{
X509ExtensionCollection extensions = new X509ExtensionCollection();
SubjectAlternativeNameBuilder builder = new SubjectAlternativeNameBuilder();
builder.AddDnsName(targetName);
extensions.Add(builder.Build());
extensions.Add(s_eeConstraints);
extensions.Add(s_eeKeyUsage);
extensions.Add(serverCertificate ? s_tlsServerEku : s_tlsClientEku);
return(extensions);
}
public static X509Certificate2 CreateSelfSignedCertificate(string subject)
{
var oids = new OidCollection();
oids.Add(new Oid("1.3.6.1.5.5.7.3.2")); // client auth
var extensions = new X509ExtensionCollection();
extensions.Add(new X509EnhancedKeyUsageExtension(oids, true));
var cgr = new CertificateGenerationRequest()
{
Subject = subject,
Extensions = extensions,
ExpirationLength = TimeSpan.FromDays(365 * 5),
KeySize = 2048
};
var cert = CertificateGenerator.CreateSelfSignedCertificate(cgr);
X509Store store = new X509Store(StoreName.My, StoreLocation.LocalMachine);
try
{
store.Open(OpenFlags.ReadWrite);
store.Add(cert);
}
finally
{
store.Close();
}
return(cert);
}
/// <summary>
///
/// </summary>
/// <param name="rawData"></param>
/// <returns></returns>
/// <exception cref="ArgumentNullException"></exception>
/// <exception cref="InvalidDataException"></exception>
public static X509ExtensionCollection DecodeX509Extensions(Byte[] rawData)
{
if (rawData == null)
{
throw new ArgumentNullException("rawData");
}
Asn1Reader asn = new Asn1Reader(rawData);
if (asn.Tag != 48)
{
throw new InvalidDataException();
}
X509ExtensionCollection exts = new X509ExtensionCollection();
if (!asn.MoveNext())
{
throw new Asn1InvalidTagException();
}
if (asn.NextOffset == 0)
{
return(exts);
}
do
{
exts.Add(DecodeX509Extension(asn.GetTagRawData()));
} while (asn.MoveNextCurrentLevel());
return(exts);
}
public X509ExtensionCollection GetExtensions()
{
var coll = new X509ExtensionCollection();
if (!HasExtensions)
{
return(coll);
}
X509ExtensionAsn[] rawExtensions = _parsedData.Extensions;
foreach (X509ExtensionAsn rawExtension in rawExtensions)
{
X509Extension extension = new X509Extension(
rawExtension.ExtnId,
rawExtension.ExtnValue.ToArray(),
rawExtension.Critical);
// Currently there are no extensions defined.
// Should this dip into CryptoConfig or other extensible
// mechanisms for the CopyTo rich type uplift?
coll.Add(extension);
}
return(coll);
}
void getAttributes(Asn1Reader asn)
{
asn.MoveNext();
if (asn.PayloadLength == 0)
{
return;
}
do
{
X509Attribute attribute = X509Attribute.Decode(asn.GetTagRawData());
if (attribute.Oid.Value == X509ExtensionOid.CertificateExtensions)
{
//Extensions
var extensions = new X509ExtensionCollection();
extensions.Decode(attribute.RawData);
foreach (X509Extension extension in extensions)
{
_extensions.Add(extension);
}
}
else
{
_attributes.Add(attribute);
}
} while (asn.MoveNextCurrentLevel());
}
public void Indexer_Int()
{
X509ExtensionCollection c = new X509ExtensionCollection();
c.Add(extn_empty);
Assert.AreEqual(extn_empty, c[0], "0");
}
/// <summary>
/// Decodes ASN.1-encoded byte array that represents a collection of <see cref="X509Extension"/> objects.
/// </summary>
/// <param name="extensions">Destination collection where decoded extensions will be added.</param>
/// <param name="rawData">ASN.1-encoded byte array that represents extension collection.</param>
/// <exception cref="Asn1InvalidTagException">Decoder encountered an unexpected ASN.1 type identifier.</exception>
/// <exception cref="ArgumentNullException">
/// <strong>extensions</strong> and/or <strong>rawData</strong> parameter is null.
/// </exception>
/// <remarks>If current collection contains items, decoded items will be appended to existing items.</remarks>
public static void Decode(this X509ExtensionCollection extensions, Byte[] rawData)
{
if (extensions == null)
{
throw new ArgumentNullException(nameof(extensions));
}
if (rawData == null)
{
throw new ArgumentNullException(nameof(rawData));
}
Asn1Reader asn = new Asn1Reader(rawData);
if (asn.Tag != 48)
{
throw new Asn1InvalidTagException();
}
if (!asn.MoveNext() || asn.NextOffset == 0)
{
return;
}
do
{
extensions.Add(X509ExtensionExtensions.Decode(asn.GetTagRawData()));
} while (asn.MoveNextCurrentLevel());
}
public void Add()
{
X509ExtensionCollection c = new X509ExtensionCollection();
Assert.AreEqual(0, c.Count, "Count-0");
c.Add(extn_empty);
Assert.AreEqual(1, c.Count, "Count-1");
}
public void Indexer_String()
{
X509ExtensionCollection c = new X509ExtensionCollection();
c.Add(extn_empty);
Assert.IsNull(c[String.Empty]);
Assert.IsNull(c ["1.2.3"]);
Assert.AreEqual(extn_empty, c["1.2"], "0");
}
public void ICollection_CopyTo()
{
X509ExtensionCollection c = new X509ExtensionCollection();
c.Add(extn_empty);
X509Extension[] array = new X509Extension[1];
(c as ICollection).CopyTo(array, 0);
Assert.AreEqual(extn_empty, array[0], "0");
}
/// <summary>
/// Generate a self-signed CA certificate
/// </summary>
/// <param name="subject">The X500 subject string</param>
/// <param name="rsaKeySize">The size of the RSA key to generate</param>
/// <param name="hashAlgorithm">Specify the signature hash algorithm</param>
/// <returns>An X509Certificate2 object containing the full certificate</returns>
public static X509Certificate2 GenerateCACert(string subject, int rsaKeySize, CertificateHashAlgorithm hashAlgorithm)
{
X509ExtensionCollection exts = new X509ExtensionCollection();
DateTime dt = DateTime.Now.AddYears(-1);
exts.Add(new X509BasicConstraintsExtension(true, false, 0, false));
return(builder.CreateCert(null, new X500DistinguishedName(subject), null, false, rsaKeySize, hashAlgorithm, dt, dt.AddYears(10), exts));
}
internal static (X509Certificate2 certificate, X509Certificate2Collection) GenerateCertificates(string targetName, [CallerMemberName] string?testName = null)
{
if (PlatformDetection.IsWindows && testName != null)
{
CleanupCertificates(testName);
}
X509Certificate2Collection chain = new X509Certificate2Collection();
X509ExtensionCollection extensions = new X509ExtensionCollection();
SubjectAlternativeNameBuilder builder = new SubjectAlternativeNameBuilder();
builder.AddDnsName(targetName);
extensions.Add(builder.Build());
extensions.Add(s_eeConstraints);
extensions.Add(s_eeKeyUsage);
extensions.Add(s_tlsServerEku);
CertificateAuthority.BuildPrivatePki(
PkiOptions.IssuerRevocationViaCrl,
out RevocationResponder responder,
out CertificateAuthority root,
out CertificateAuthority intermediate,
out X509Certificate2 endEntity,
subjectName: targetName,
testName: testName,
keySize: 2048,
extensions: extensions);
chain.Add(intermediate.CloneIssuerCert());
chain.Add(root.CloneIssuerCert());
responder.Dispose();
root.Dispose();
intermediate.Dispose();
if (PlatformDetection.IsWindows)
{
endEntity = new X509Certificate2(endEntity.Export(X509ContentType.Pfx));
}
return(endEntity, chain);
}
public static void AddRange(this X509ExtensionCollection exts, IEnumerable <X509Extension> extensions)
{
if (exts == null)
{
return;
}
foreach (X509Extension e in extensions)
{
exts.Add(e);
}
}
/// <summary>
/// Create a CRL builder initialized with a decoded CRL.
/// </summary>
/// <param name="crl">The decoded CRL</param>
private CrlBuilder(IX509CRL crl)
{
IssuerName = crl.IssuerName;
HashAlgorithmName = crl.HashAlgorithmName;
ThisUpdate = crl.ThisUpdate;
NextUpdate = crl.NextUpdate;
RawData = crl.RawData;
m_revokedCertificates = new List <RevokedCertificate>(crl.RevokedCertificates);
m_crlExtensions = new X509ExtensionCollection();
foreach (var extension in crl.CrlExtensions)
{
m_crlExtensions.Add(extension);
}
}
private static X509Certificate2 CreateCertificateAuthority()
{
CspParameters parameters = new CspParameters()
{
ProviderName = "Microsoft Enhanced RSA and AES Cryptographic Provider",
ProviderType = 24,
KeyContainerName = Guid.NewGuid().ToString(),
KeyNumber = (int)KeyNumber.Signature,
Flags = CspProviderFlags.UseMachineKeyStore
};
var extensions = new X509ExtensionCollection();
extensions.Add(new X509BasicConstraintsExtension(true, false, 0, false));
extensions.Add(new X509KeyUsageExtension(
X509KeyUsageFlags.CrlSign |
X509KeyUsageFlags.DataEncipherment |
X509KeyUsageFlags.DigitalSignature |
X509KeyUsageFlags.KeyAgreement |
X509KeyUsageFlags.KeyCertSign |
X509KeyUsageFlags.KeyEncipherment |
X509KeyUsageFlags.NonRepudiation, false));
var cgr = new CertificateGenerationRequest()
{
Subject = "Syfuhs Industries Certificate Authority",
Parameters = parameters,
SignatureAlgorithm = "1.2.840.113549.1.1.11",
ExpirationLength = TimeSpan.FromDays(365 * 20),
KeySize = 2048,
Extensions = extensions
};
var cert = CertificateGenerator.CreateSelfSignedCertificate(cgr);
return(cert);
}
/// <summary>
/// Adds a collection of <see cref="X509Extension"/> objects to existing collection.
/// </summary>
/// <param name="extensions">Destination collection where items will be added.</param>
/// <param name="itemsToAdd">A source collection of items to add to destination.</param>
/// <exception cref="ArgumentNullException">
/// <strong>extensions</strong> and/or <strong>itemsToAdd</strong> is null.
/// </exception>
public static void AddRange(this X509ExtensionCollection extensions, IEnumerable <X509Extension> itemsToAdd)
{
if (extensions == null)
{
throw new ArgumentNullException(nameof(extensions));
}
if (itemsToAdd == null)
{
throw new ArgumentNullException(nameof(itemsToAdd));
}
foreach (X509Extension e in itemsToAdd)
{
extensions.Add(e);
}
}
/// <summary>
/// Create CRL from IX509CRL interface.
/// </summary>
/// <param name="crl"></param>
public X509CRL(IX509CRL crl)
{
m_decoded = true;
m_issuerName = crl.IssuerName;
m_hashAlgorithmName = crl.HashAlgorithmName;
m_thisUpdate = crl.ThisUpdate;
m_nextUpdate = crl.NextUpdate;
m_revokedCertificates = new List <RevokedCertificate>(crl.RevokedCertificates);
m_crlExtensions = new X509ExtensionCollection();
foreach (var extension in crl.CrlExtensions)
{
m_crlExtensions.Add(extension);
}
RawData = crl.RawData;
}
internal static void RemoveAt(this X509ExtensionCollection exts, Int32 index)
{
if (exts == null || index >= exts.Count)
{
return;
}
List <X509Extension> e = new List <X509Extension>(exts.Cast <X509Extension>());
e.RemoveAt(index);
exts = new X509ExtensionCollection();
foreach (X509Extension ext in e)
{
exts.Add(ext);
}
}
void processExtensions()
{
foreach (X509Extension extension in Extensions)
{
if (_excludedExtensions.Contains(extension.Oid.Value))
{
continue;
}
_extensions.Add(extension.ConvertExtension());
}
finalExtensions = new X509ExtensionCollection();
foreach (var extension in _extensions)
{
finalExtensions.Add(extension);
}
}
/// <summary>
/// Returns all extensions
/// </summary>
/// <returns></returns>
private X509ExtensionCollection GetExtensions()
{
var extensions = new X509ExtensionCollection();
var attr = GetAttribute(OidAttributes.Extension);
if (attr != null)
{
var asn1Object = Asn1Object.FromByteArray(attr.Values[0].RawData);
var asn1Sequence = Asn1Sequence.GetInstance(asn1Object);
foreach (Asn1Encodable item in asn1Sequence)
{
var ext = QualificationExtension(item);
extensions.Add(ext);
}
}
return(extensions);
}
void decodePkcs7()
{
ExternalData = new PKCS7SignedMessage(RawData);
Version = ((X509CertificateRequest[])ExternalData.Content)[0].Version;
SubjectDn = ((X509CertificateRequest[])ExternalData.Content)[0].SubjectDn;
PublicKey = ((X509CertificateRequest[])ExternalData.Content)[0].PublicKey;
SignatureIsValid = ((X509CertificateRequest[])ExternalData.Content)[0].SignatureIsValid;
SignatureAlgorithm = ((X509CertificateRequest[])ExternalData.Content)[0].SignatureAlgorithm;
foreach (X509Attribute attrib in ((X509CertificateRequest[])ExternalData.Content)[0].Attributes)
{
_attribs.Add(attrib);
}
foreach (X509Extension ext in ((X509CertificateRequest[])ExternalData.Content)[0].Extensions)
{
exts.Add(ext);
}
}
/// <summary>
/// Take an existing certificate, clone its details and resign with a new root CA
/// </summary>
/// <param name="toClone">The certificate to clone</param>
/// <param name="rootCert">The root CA certificate to sign with</param>
/// <param name="newSerial">True to generate a new serial for this certificate</param>
/// <param name="rsaKeySize">The size of the RSA key to generate</param>
/// <param name="hashAlgorithm">Specify the signature hash algorithm</param>
/// <returns></returns>
public static X509Certificate2 CloneAndSignCertificate(X509Certificate toClone, X509Certificate2 rootCert, bool newSerial, int rsaKeySize, CertificateHashAlgorithm hashAlgorithm)
{
X509Certificate2 cert2 = new X509Certificate2(toClone.Export(X509ContentType.Cert));
X509ExtensionCollection extensions = new X509ExtensionCollection();
foreach (var ext in cert2.Extensions)
{
// Remove CRL distribution locations and authority information, they tend to break SSL negotiation
if ((ext.Oid.Value != szOID_CRL_DISTRIBUTION) && (ext.Oid.Value != szOID_AUTHORITY_INFO))
{
extensions.Add(ext);
}
}
return(CertificateBuilder.CreateCert(rootCert, cert2.SubjectName, newSerial ? null : cert2.GetSerialNumber(),
rsaKeySize, hashAlgorithm, cert2.NotBefore, cert2.NotAfter, extensions));
}
/// <summary>
/// Converts generic X.509 extension objects to specialized certificate extension objects
/// inherited from <see cref="X509Extension"/> class that provide extension-specific information.
/// </summary>
/// <param name="cert">Certificate.</param>
/// <exception cref="ArgumentNullException">
/// <strong>cert</strong> parameter is null reference.
/// </exception>
/// <returns>A collection of certificate extensions</returns>
/// <remarks>
/// This method can transform the following X.509 certificate extensions:
/// <list type="bullet">
/// <item><description><see cref="X509CertificateTemplateExtension"/></description></item>
/// <item><description><see cref="X509ApplicationPoliciesExtension"/></description></item>
/// <item><description><see cref="X509ApplicationPolicyMappingsExtension"/></description></item>
/// <item><description><see cref="X509ApplicationPolicyConstraintsExtension"/></description></item>
/// <item><description><see cref="X509AuthorityInformationAccessExtension"/></description></item>
/// <item><description><see cref="X509NonceExtension"/></description></item>
/// <item><description><see cref="X509CRLReferenceExtension"/></description></item>
/// <item><description><see cref="X509ArchiveCutoffExtension"/></description></item>
/// <item><description><see cref="X509ServiceLocatorExtension"/></description></item>
/// <item><description><see cref="X509SubjectKeyIdentifierExtension"/></description></item>
/// <item><description><see cref="X509KeyUsageExtension"/></description></item>
/// <item><description><see cref="X509SubjectAlternativeNamesExtension"/></description></item>
/// <item><description><see cref="X509IssuerAlternativeNamesExtension"/></description></item>
/// <item><description><see cref="X509BasicConstraintsExtension"/></description></item>
/// <item><description><see cref="X509CRLNumberExtension"/></description></item>
/// <item><description><see cref="X509NameConstraintsExtension"/></description></item>
/// <item><description><see cref="X509CRLDistributionPointsExtension"/></description></item>
/// <item><description><see cref="X509CertificatePoliciesExtension"/></description></item>
/// <item><description><see cref="X509CertificatePolicyMappingsExtension"/></description></item>
/// <item><description><see cref="X509AuthorityKeyIdentifierExtension"/></description></item>
/// <item><description><see cref="X509CertificatePolicyConstraintsExtension"/></description></item>
/// <item><description><see cref="X509EnhancedKeyUsageExtension"/></description></item>
/// <item><description><see cref="X509FreshestCRLExtension"/></description></item>
/// </list>
/// Non-supported extensions will be returned as an <see cref="X509Extension"/> object.
/// </remarks>
public static X509ExtensionCollection ResolveExtensions(this X509Certificate2 cert)
{
if (cert == null)
{
throw new ArgumentNullException(nameof(cert));
}
if (cert.Extensions.Count == 0)
{
return(cert.Extensions);
}
X509ExtensionCollection extensions = new X509ExtensionCollection();
foreach (var ext in cert.Extensions)
{
extensions.Add(ext.ConvertExtension());
}
return(extensions);
}
internal static X509ExtensionCollection ShallowCopy(X509ExtensionCollection existing, bool preserveNull)
{
if (preserveNull && existing == null)
{
return(null);
}
var coll = new X509ExtensionCollection();
if (existing == null)
{
return(coll);
}
foreach (var extn in existing)
{
coll.Add(extn);
}
return(coll);
}
private static System.Security.Cryptography.X509Certificates.X509Certificate2 CreateSubordinate()
{
var oids = new OidCollection();
oids.Add(new Oid("1.3.6.1.5.5.7.3.2")); // client auth
oids.Add(new Oid("1.3.6.1.4.1.311.20.2.2")); // smart card login
var extensions = new X509ExtensionCollection();
extensions.Add(new X509EnhancedKeyUsageExtension(oids, true));
var cgr = new CertificateGenerationRequest()
{
Subject = "*****@*****.**",
Extensions = extensions,
ExpirationLength = TimeSpan.FromDays(365 * 5),
KeySize = 2048
};
var cert = CertificateGenerator.CreateSelfSignedCertificate(cgr);
return(cert);
}
/// <summary>
/// Decodes ASN.1-encoded byte array that represents a collection of <see cref="X509Extension"/> objects.
/// </summary>
/// <param name="extensions">Destination collection where decoded extensions will be added.</param>
/// <param name="asn">ASN.1 reader which points to the beginning of the extenstion collection structure.</param>
/// <exception cref="Asn1InvalidTagException">Decoder encountered an unexpected ASN.1 type identifier.</exception>
/// <exception cref="ArgumentNullException">
/// <strong>extensions</strong> and/or <strong>asn</strong> parameter is null.
/// </exception>
/// <remarks> If current collection contains items, decoded items will be appended to existing items.</remarks>
public static void Decode(this X509ExtensionCollection extensions, Asn1Reader asn)
{
if (extensions == null)
{
throw new ArgumentNullException(nameof(extensions));
}
if (asn == null)
{
throw new ArgumentNullException(nameof(asn));
}
Int32 offset = asn.Offset;
if (!asn.MoveNext() || asn.PayloadLength == 0)
{
return;
}
do
{
extensions.Add(X509ExtensionExtensions.Decode(asn));
} while (asn.MoveNextSibling());
asn.Seek(offset);
}
private void buttonCreate_Click(object sender, EventArgs e)
{
DialogResult = DialogResult.OK;
int rsaKeySize = 0;
if (radioButtonSimpleCN.Checked && String.IsNullOrWhiteSpace(textBoxCN.Text))
{
MessageBox.Show(this, CANAPE.Properties.Resources.CreateCertForm_MustSpecifyCN,
CANAPE.Properties.Resources.MessageBox_ErrorString, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else if (radioButtonTemplate.Checked && _templateCert == null)
{
MessageBox.Show(this, CANAPE.Properties.Resources.CreateCertForm_MustSpecifyTemplate,
CANAPE.Properties.Resources.MessageBox_ErrorString, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else if (radioButtonSpecifyCA.Checked && _specifyCert == null)
{
MessageBox.Show(this, CANAPE.Properties.Resources.CreateCertForm_MustSpecifyCA,
CANAPE.Properties.Resources.MessageBox_ErrorString, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else if (!int.TryParse(comboBoxRsaKeySize.Text, out rsaKeySize))
{
MessageBox.Show(this, CANAPE.Properties.Resources.CreateCertForm_MustSpecifyAValidRSAKeySize,
CANAPE.Properties.Resources.MessageBox_ErrorString, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
try
{
X509Certificate2 rootCert = null;
if (radioButtonSpecifyCA.Checked)
{
rootCert = _specifyCert;
}
else if (radioButtonDefaultCA.Checked)
{
rootCert = CertManager.GetRootCert();
}
else
{
// Self signed
}
if (radioButtonTemplate.Checked)
{
Certificate = CertificateUtils.CloneAndSignCertificate(_templateCert, rootCert, false, rsaKeySize, (CertificateHashAlgorithm)comboBoxHash.SelectedItem);
}
else
{
X509ExtensionCollection exts = new X509ExtensionCollection();
if (checkBoxCA.Checked)
{
exts.Add(new X509BasicConstraintsExtension(true, false, 0, true));
}
DateTime notBefore = DateTime.Now.Subtract(TimeSpan.FromDays(1));
Certificate = CertificateUtils.CreateCert(rootCert,
new X500DistinguishedName(radioButtonSubject.Checked ? textBoxCN.Text : String.Format("CN={0}", textBoxCN.Text)), null, false, rsaKeySize,
(CertificateHashAlgorithm)comboBoxHash.SelectedItem, notBefore, notBefore.AddYears(10), exts);
}
}
catch (Win32Exception ex)
{
MessageBox.Show(ex.Message, CANAPE.Properties.Resources.MessageBox_ErrorString,
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (CryptographicException ex)
{
MessageBox.Show(ex.Message, CANAPE.Properties.Resources.MessageBox_ErrorString,
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
public void Add_Null()
{
empty.Add(null);
}