C# 如何获取带有标题的 XML (<?xml version="1.0"...)？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/14839630/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to get XML with header (<?xml version="1.0"...)?
提问by ispiro
Consider the following simple code which creates an XML document and displays it.
考虑以下创建 XML 文档并显示它的简单代码。
XmlDocument xml = new XmlDocument();
XmlElement root = xml.CreateElement("root");
xml.AppendChild(root);
XmlComment comment = xml.CreateComment("Comment");
root.AppendChild(comment);
textBox1.Text = xml.OuterXml;
it displays, as expected:
它按预期显示：
<root><!--Comment--></root>
It doesn't, however, display the
但是，它不显示
<?xml version="1.0" encoding="UTF-8"?>
So how can I get that as well?
那么我怎样才能得到它呢？
采纳答案by Sergey Brunov
Create an XML-declaration using XmlDocument.CreateXmlDeclaration Method:
使用XmlDocument.CreateXmlDeclaration 方法创建 XML 声明：
XmlNode docNode = xml.CreateXmlDeclaration("1.0", "UTF-8", null);
xml.AppendChild(docNode);
Note: please take a look at the documentation for the method, especiallyfor encodingparameter: there are special requirements for values of this parameter.
注意：方法请看文档，特别是encoding参数：对这个参数的取值有特殊要求。
回答by Nicholas Carey
You need to use an XmlWriter (which writes the XML declaration by default). You should note that that C# strings are UTF-16 and your XML declaration says that the document is UTF-8 encoded. That discrepancy can cause problems. Here's an example, writing to a file that gives the result you expect:
您需要使用 XmlWriter（默认情况下编写 XML 声明）。您应该注意，C# 字符串是 UTF-16，而您的 XML 声明表示该文档是 UTF-8 编码的。这种差异会导致问题。这是一个例子，写入一个文件，给出你期望的结果：
XmlDocument xml = new XmlDocument();
XmlElement root = xml.CreateElement("root");
xml.AppendChild(root);
XmlComment comment = xml.CreateComment("Comment");
root.AppendChild(comment);
XmlWriterSettings settings = new XmlWriterSettings
{
Encoding = Encoding.UTF8,
ConformanceLevel = ConformanceLevel.Document,
OmitXmlDeclaration = false,
CloseOutput = true,
Indent = true,
IndentChars = " ",
NewLineHandling = NewLineHandling.Replace
};
using ( StreamWriter sw = File.CreateText("output.xml") )
using ( XmlWriter writer = XmlWriter.Create(sw,settings))
{
xml.WriteContentTo(writer);
writer.Close() ;
}
string document = File.ReadAllText( "output.xml") ;
回答by Asif
XmlDeclaration xmldecl;
xmldecl = xmlDocument.CreateXmlDeclaration("1.0", "UTF-8", null);
XmlElement root = xmlDocument.DocumentElement;
xmlDocument.InsertBefore(xmldecl, root);
