How can I add prefixes to xml output using C#?

Question

I wanna add prefixes like cbc: cac: iac: to xml output to see output like this - <cbc:ID>custom value</cbc:ID>  but  everytime it looks like <ID>custom value</ID>. Also I've used namespace urls in CreateElement method from XML Document but everytime the output is adding these urls after every prefix and I don't need this. Could u say to me how can I add prefixes in xml like that?

Answer 1

If you are using XML serialization code will look like this. When no namespace use [XmlElement(Namespace = "")]

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Serialization;

namespace ConsoleApp2
{
    class Program
    {
        const string FILENAME = @"c:\temp\test.xml";
        static void Main(string[] args)
        {
            XmlSerializerNamespaces namespaces = new XmlSerializerNamespaces();
            namespaces.Add(string.Empty, "urn:carrier:names:specification:ubl:schema:xsd:CarrierDealerContractorInvoice-1.0");
            namespaces.Add("cac", "urn:oasis:names:draft:ubl:schema:xsd:CommonAggregateComponents-2");
            namespaces.Add("cbc", "urn:oasis:names:draft:ubl:schema:xsd:CommonBasicComponents-2");
            namespaces.Add("ibc", "urn:carrier:names:specification:ubl:schema:xsd:CarrierDealerContractorInvoiceBasicComponents-1.0");
            namespaces.Add("iac", "urn:carrier:names:specification:ubl:schema:xsd:CarrierDealerContractorInvoiceAggregateComponents-1.0");
            namespaces.Add("xsi", "http://www.w3.org/2001/XMLSchema-instance");

            XmlWriterSettings settings = new XmlWriterSettings();
            settings.Indent = true;

            XmlWriter writer = XmlWriter.Create(FILENAME, settings);
            XmlSerializer serializer = new XmlSerializer(typeof(DealerContractorInvoice));

            DealerContractorInvoice invoice = new DealerContractorInvoice();
            serializer.Serialize(writer, invoice, namespaces);
        }
    }
    [XmlRoot(Namespace = "urn:oasis:names:draft:ubl:schema:xsd:CommonBasicComponents-2")]
    public class DealerContractorInvoice
    {
        [XmlElement(Namespace = "urn: carrier:names: specification:ubl: schema:xsd: CarrierDealerContractorInvoiceAggregateComponents - 1.0")]
        public string ID { get; set; }

        [XmlElement(Namespace = "urn:carrier:names:specification:ubl:schema:xsd:CarrierDealerContractorInvoiceAggregateComponents-1.0")]
        DealerContractorInvoiceLine DealerContractorInvoiceLine { get; set; }
    }
    public class DealerContractorInvoiceLine
    {
    }
}

Using xml linq :

       const string FILENAME = @"c:\temp\test.xml";
        static void Main(string[] args)
        {
            string ident = "<?xml version='1.0'?>" +
                           "<DealerContractorInvoice " +
                              " xmlns=\"urn: carrier: names: specification: ubl: schema: xsd: CarrierDealerContractorInvoice - 1.0\"" +
                              " xmlns:cac=\"urn: oasis: names: draft: ubl: schema: xsd: CommonAggregateComponents - 2\"" +
                              " xmlns:cbc=\"urn: oasis: names: draft: ubl: schema: xsd: CommonBasicComponents - 2\"" +
                              " xmlns:ibc=\"urn: carrier: names: specification: ubl: schema: xsd: CarrierDealerContractorInvoiceBasicComponents - 1.0\"" +
                              " xmlns:iac=\"urn: carrier: names: specification: ubl: schema: xsd: CarrierDealerContractorInvoiceAggregateComponents - 1.0\"" +
                              " xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"" +
                              " xsi:schemaLocation=\"urn:carrier:names:specification:ubl:schema:xsd:CarrierDealerContractorInvoice-1.0 ../../src/xsd/runtime/maindoc/UBL-CarrierDealerContractorInvoice-1.0.xsd\"" +
                           "/>";

            XDocument doc = XDocument.Parse(ident);
            XElement invoice = doc.Root;

            //use when no prefix
            XNamespace ns = invoice.GetDefaultNamespace();
            XNamespace nsCbc = invoice.GetNamespaceOfPrefix("cbc");

            XElement id = new XElement(nsCbc + "ID");
            invoice.Add(id);
        }