如何在 C# 中对没有 BOM 前导码的签名 xml 文件进行 UTF8 编码

Question

我有一个对我的 xml 文件进行签名的函数，该文件采用 utf-8 编码，但是当我应用该符号时，它显示“utf-8 with Boom”（错误版本），我如何正确保存文件private static void FirmarDocumentoComplemento(string pathXmlDocument, string pathCert, string passCert, string pathXmlSignet, string ruta, string rut, string fecha, string tipo){    XmlDocument documentXml = new XmlDocument();    documentXml.Load(pathXmlDocument);    SignedXml firmado = new SignedXml(documentXml);    var cert = RSA_helper.GetX509Certificate(pathCert, passCert);    firmado.SigningKey = (RSA)cert.PrivateKey;    firmado.SignedInfo.SignatureMethod = "http://www.w3.org/2000/09/xmldsig#rsa-sha1";    //digest info    Reference reference = new Reference();    reference.Uri = "";    reference.DigestMethod = "http://www.w3.org/2000/09/xmldsig#sha1";    firmado.AddReference(reference);    // with the public key will be added in the signature part.     KeyInfo keyInfo = new KeyInfo();    keyInfo.AddClause(new RSAKeyValue((RSA)cert.PrivateKey));    keyInfo.AddClause(new KeyInfoX509Data(cert));    firmado.KeyInfo = keyInfo;    firmado.ComputeSignature();    XmlElement xmlDigitalSignature = firmado.GetXml();    // buscamos el ultimo elemento del documento para agregarle la firma    XmlElement elemento = (XmlElement)documentXml.SelectSingleNode(@"//datos_complementarios_declaracion_ingreso/representantes[last()]");    XmlNode parent = elemento.ParentNode;    parent.InsertAfter(xmlDigitalSignature, elemento);    string ruta_completa = ruta + rut + " - " + tipo + " - " + fecha + " - N - " + "Complemento Firmado.xml";    documentXml.Save(ruta_completa);}

Answer 1

XmlWriterSettings settings = new XmlWriterSettings();
settings.Indent = true;
settings.Encoding = new UTF8Encoding(false);string ruta_completa = $"{ruta}{rut} - {tipo} - {fecha} - N - Complemento Firmado.xml";

XmlWriter writer = XmlWriter.Create(ruta_completa, settings);
doc.Save(writer);

您应该使用XmlTextWriter的实例编写文档，并在其构造函数中传递一个XmlWriterSettings实例，其中您将Encoding属性显式设置为不带 BOM 前导码的UTF8Encoding实例