如何使XMLDOMDocument包含XML声明？

Question

当XMLDOMDocument自行保存时,如何让它包含XML声明,例如:

• <?xml version="1.0" encoding="UTF-8" ?>
• <?xml version="1.0" encoding="UTF-16" ?>
• <?xml version="1.0" encoding="UCS-2" ?>
• <?xml version="1.0" encoding="UCS-4" ?>
• <?xml version="1.0" encoding="ISO-10646-UCS-2" ?>
• <?xml version="1.0" encoding="UNICODE-1-1-UTF-8" ?>
• <?xml version="1.0" encoding="UNICODE-2-0-UTF-16" ?>
• <?xml version="1.0" encoding="UNICODE-2-0-UTF-8" ?>
• <?xml version="1.0" encoding="US-ASCII" ?>
• <?xml version="1.0" encoding="ISO-8859-1" ?>
• <?xml version="1.0" encoding="WINDOWS-1250" ?>

XMLDOMDomcument对象正在内存中创建(即xml不是从某些外部源加载的):

{
   IXMLDOMDocument2 doc = new DOMDocument60();

   //add nodes to the doc
   ...

   doc.Save(saveTarget);
}

没有xml声明,你只能获得body xml,例如:

<Customer>
   ...
</Customer>

而不是完整的XML文档:

<?xml version="1.0" encoding="US-ASCII" ?>
<Customer>
   ...
</Customer>

问题2

如何控制XMLDOMDocument在保存到流时将使用的编码？

Answer 1

您需要使用MXXMLWriter60,而不是直接保存它.对不起,我没有C#示例,但这里是VB.Net等价物.有关详细信息,请参阅IMXWriter.

' Create and load a DOMDocument object.

Dim xmlDoc As New DOMDocument60
xmlDoc.loadXML("<doc><one>test1</one><two>test2</two></doc>")

' Set properties on the XML writer - including BOM, XML declaration and encoding

Dim wrt As New MXXMLWriter60
wrt.byteOrderMark = True
wrt.omitXMLDeclaration = False
wrt.encoding = "US-ASCII"
wrt.indent = True

' Set the XML writer to the SAX content handler.

Dim rdr As New SAXXMLReader60
Set rdr.contentHandler = wrt
Set rdr.dtdHandler = wrt
Set rdr.errorHandler = wrt
rdr.putProperty "http://xml.org/sax/properties/lexical-handler", wrt
rdr.putProperty "http://xml.org/sax/properties/declaration-handler", wrt

' Now pass the DOM through the SAX handler, and it will call the writer

rdr.parse xmlDoc

' Let the writer do its thing

Dim iFileNo As Integer
iFileNo = FreeFile
Open App.Path + "\saved.xml" For Output As #iFileNo
Print #iFileNo, wrt.output
Close #iFileNo