/// <summary>
/// Initializes a new instance of <strong>SignedCmsBuilder</strong> from existing Signed CMS. Data from existing CMS
/// is copied to builder and can be modified.
/// </summary>
/// <param name="cms">Existing Signed CMS message.</param>
/// <exception cref="ArgumentNullException">
/// <srong>cms</srong> parameter is null.
/// </exception>
public SignedCmsBuilder(DefaultSignedPkcs7 cms)
{
if (cms == null)
{
throw new ArgumentNullException(nameof(cms));
}
_contentType = cms.ContentType;
_content = cms.Content;
DigestAlgorithms.AddRange(cms.DigestAlgorithms);
Certificates.AddRange(cms.Certificates);
RevocationLists.AddRange(cms.RevocationLists);
SignerInfos.AddRange(cms.SignerInfos);
}