尝试以下：
using System;using System.Collections.Generic;using System.IO;using System.Linq;using System.Net;using System.Security.Cryptography.X509Certificates;using System.Security.Cryptography.Xml;using System.Text;using System.Threading.Tasks;using System.Xml;namespace Certificate{ class Program { const string FILENAME = @"c:temptest.xml"; static void Main(string[] args) { Xmldocument doc = new Xmldocument(); CreateSoap(doc); XmlElement assertion = (XmlElement)(doc.GetElementsByTagName("saml2:Assertion")[0]); XmlElement security = (XmlElement)(doc.GetElementsByTagName("wsse:Security")[0]); //added 10-20-17 XmlElement body = (XmlElement)(doc.GetElementsByTagName("soap:Body")[0]); using (WebClient client = new WebClient()) { byte[] xmlBytes = client.DownloadData(FILENAME); body.InnerXml = Encoding.UTF8.GetString(xmlBytes); } string pfxpath = @"D:CertificatePrivate-cert.pfx"; X509Certificate2 cert = new X509Certificate2(File.ReadAllBytes(pfxpath), "123456789"); SignXmlWithCertificate(assertion, cert); SignXmlWithCertificate(security, cert); //added 10-20-17 XmlElement subject = doc.CreateElement("Subject", "saml2"); assertion.AppendChild(subject); CreateSubject(subject); File.WriteAllText(@"D:Certificatedigitallysigned.xml", doc.OuterXml); } public static void CreateSoap(Xmldocument doc) { DateTime date = DateTime.Now; string soap = string.Format( "<?xml version="1.0"?>" + "<soap:Envelope" + " xmlns:soap="http://www.w3.org/2003/05/soap-envelope"" + " xmlns:wsse11="http://docs.oasisopen.org/wss/oasis-wss-wssecurity-secext-1.1.xsd"" + " xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd"" + " xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wsswssecurity-utility-1.0.xsd"" + " xmlns:xs="http://www.w3.org/2001/XMLSchema"" + " xmlns:ds="http://www.w3.org/2000/09/xmldsig#"" + " xmlns:saml="urn:oasis:names:tc:SAML:1.0:assertion"" + " xmlns:exc14n="http://www.w3.org/2001/10/xml-exc-c14n#">" + "<soap:Header>" + "<To mustUnderstand="true"" + " xmlns="http://www.w3.org/2005/08/addressing">https://localhost:443/Gateway/PatientDiscovery/1_0/NwHINService/NwHINPatientDiscovery" + "</To>" + "<Action mustUnderstand="true"" + " xmlns="http://www.w3.org/2005/08/addressing">urn:hl7-org:v3:PRPA_IN201305UV02:CrossGatewayPatientDiscovery" + "</Action>" + "<ReplyTo mustUnderstand="true"" + " xmlns="http://www.w3.org/2005/08/addressing">" + "<Address>http://www.w3.org/2005/08/addressing/anonymous</Address>" + "</ReplyTo>" + "<MessageID mustUnderstand="true"" + " xmlns="http://www.w3.org/2005/08/addressing">461433e3-4591-453b-9eb6-791c7f5ff882" + "</MessageID>" + "<wsse:Security soap:mustUnderstand="true">" + "<wsu:Timestamp wsu:Id="_1"" + " xmlns:ns17="http://docs.oasis-open.org/ws-sx/wssecureconversation/200512"" + " xmlns:ns16="http://schemas.xmlsoap.org/soap/envelope/">" + "<wsu:Created>2012-06-08T18:31:44Z</wsu:Created>" + "<wsu:Expires>2012-06-08T18:36:44Z</wsu:Expires>" + "</wsu:Timestamp>" + "<saml2:Assertion ID="_883e64a747a5449b83821913a2b189e6" IssueInstant="{0}" Version="2.0"" + " xmlns:ds="http://www.w3.org/2000/09/xmldsig#"" + " xmlns:exc14n="http://www.w3.org/2001/10/xml-excc14n#"" + " xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion"" + " xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"" + " xmlns:xs="http://www.w3.org/2001/XMLSchema">" + "<saml2:Issuer Format="urn:oasis:names:tc:SAML:1.1:nameid-format:X509SubjectName">CN=SAML User,OU=SU,O=SAML User,L=Los Angeles,ST=CA,C=US" + "</saml2:Issuer>" + "</saml2:Assertion>" + "</wsse:Security>" + "</soap:Header>" + "<soap:Body>" + "</soap:Body>" + "</soap:Envelope>", date.ToUniversalTime().ToString("yyyy-MM-ddThh:mm:ss.fffZ")); //date format //2015-03-09T21:12:02.279Z doc.LoadXml(soap); } public static void SignXmlWithCertificate(XmlElement assertion, X509Certificate2 cert) { SignedXml signedXml = new SignedXml(assertion); signedXml.SigningKey = cert.PrivateKey; Reference reference = new Reference(); reference.Uri = ""; reference.AddTransform(new XmlDsigEnvelopedSignatureTransform()); signedXml.AddReference(reference); KeyInfo keyInfo = new KeyInfo(); keyInfo.AddClause(new KeyInfoX509Data(cert)); signedXml.KeyInfo = keyInfo; signedXml.ComputeSignature(); XmlElement xmlsig = signedXml.GetXml(); assertion.AppendChild(xmlsig); } public static void CreateSubject(XmlElement xSubject) { string subject = "<saml2:NameID Format="urn:oasis:names:tc:SAML:1.1:nameidformat:X509SubjectName">UID=WilmaAnderson</saml2:NameID>" + "<saml2:SubjectConfirmation Method="urn:oasis:names:tc:SAML:2.0:cm:holder-ofkey">" + "<saml2:Subject/confirm/iationData>" + "<ds:KeyInfo>" + "<ds:KeyValue>" + "<ds:RSAKeyValue>" + "<ds:Modulus>" + "maFp5lsEHjhrQQCL0e8cbxMoDpGk1r6Uion/LA2iuD3T+sspJh8TNToQrurpFFVY/u6IzHKIk64s9894pxbwYNwv/LzRVz" + "M5pOXmCT73KGAg3Cry+QOO5KrN8hR/OXyH90/LIS77FZY+bepqD6qx4URa2/GLll08fu8xh1wPFDMCFAmb2Xz/5gK0fimUXJAWi1+PlNKML" + "nDGxHgvz5ZwiN1/QwXcQEc1mcJCimLoiCSrk7nvmqkxX4ZZ1dYzQJWdlB8Om4r9Uu96q5cZFTYwSdivLpPFKSzn/2MI9NryZC0VaIBuHRhg" + "AmspAzM90BjLO5vtiwrrfx/E3uYcMjcSEQ==" + "</ds:Modulus>" + "<ds:Exponent>AQAB</ds:Exponent>" + "</ds:RSAKeyValue>" + "</ds:KeyValue>" + "</ds:KeyInfo>" + "</saml2:Subject/confirm/iationData>" + "</saml2:Subject/confirm/iation>"; xSubject.InnerXml = subject; } }}
