XDocument.ToString()删除XML编码标记

Question

有没有办法在toString()函数中获取xml编码？

例:

xml.Save("myfile.xml");

导致

<?xml version="1.0" encoding="utf-8"?>
<Cooperations>
  <Cooperation>
    <CooperationId>xxx</CooperationId>
    <CooperationName>Allianz Konzern</CooperationName>
    <LogicalCustomers>

但

tb_output.Text = xml.toString();

导致像这样的输出

<Cooperations>
  <Cooperation>
    <CooperationId>xxx</CooperationId>
    <CooperationName>Allianz Konzern</CooperationName>
    <LogicalCustomers>
    ...

Answer 1

要么明确写出声明,要么使用StringWriter和调用Save():

using System;
using System.IO;
using System.Text;
using System.Xml.Linq;

class Test
{
    static void Main()
    {
        string xml = @"<?xml version='1.0' encoding='utf-8'?>
<Cooperations>
  <Cooperation />
</Cooperations>";

        XDocument doc = XDocument.Parse(xml);
        StringBuilder builder = new StringBuilder();
        using (TextWriter writer = new StringWriter(builder))
        {
            doc.Save(writer);
        }
        Console.WriteLine(builder);
    }
}

您可以轻松地将其添加为扩展方法:

public static string ToStringWithDeclaration(this XDocument doc)
{
    if (doc == null)
    {
        throw new ArgumentNullException("doc");
    }
    StringBuilder builder = new StringBuilder();
    using (TextWriter writer = new StringWriter(builder))
    {
        doc.Save(writer);
    }
    return builder.ToString();
}

这样做的好处是,如果没有声明,它就不会爆炸:)

然后你可以使用:

string x = doc.ToStringWithDeclaration();

请注意,这将使用utf-16作为编码,因为这是隐式编码StringWriter.您可以通过创建子类来自己影响StringWriter,例如始终使用UTF-8.

Answer 2

Declaration属性将包含XML声明.要获取内容和声明,您可以执行以下操作:

tb_output.Text = xml.Declaration.ToString() + xml.ToString()

Answer 3

用这个:

output.Text = String.Concat(xml.Declaration.ToString() , xml.ToString())