在 Python 中使用 SAX 生成 XML 输出时如何插入 DTD DOCTYPE 内容答案

【问题标题】：How to insert DTD DOCTYPE content when using SAX to generate XML output in Python在 Python 中使用 SAX 生成 XML 输出时如何插入 DTD DOCTYPE 内容
【发布时间】：2011-06-19 03:55:22
【问题描述】：

我正在尝试使用 python（实际上是 jython）xml.sax.saxutils.XMLGenerator 生成一个大型 XML 文件。我想包含 DTD 信息，但我不知道如何将 DTD 字符串传递给 SAX。这是示例 SAX 编写器类：

from xml.sax.saxutils import XMLGenerator

class xml_writer:
    def __init__(self, output, encoding):
        """
        an XML writer object that generate xml output to a file
        """
        xmlwriter = XMLGenerator(output, encoding)
        xmlwriter.startDocument()
        self._writer = xmlwriter
        self._output = output
        self._encoding = encoding

        self.attr_vals = {}
        self.attr_qnames = {}
        return

    def start_elem(self, name):
        name = unicode(name)
        attrs = AttributesNSImpl(self.attr_vals, self.attr_qnames)
        self._writer.startElementNS((None, name), name, attrs)
        self._writer._out.write('\n')
        self.attr_qnames = {}
        self.attr_vals = {}

    def end_elem(self, name):
        name = unicode(name)
        self._writer.endElementNS((None, name), name)
        self._writer._out.write('\n')

    def setAttribute(self, aname, value):
        aname = unicode(aname)
        value = unicode(value)
        self.attr_vals[(None, aname)] = value
        self.attr_qnames[(None, aname)] = aname

    def close(self):
        """
        Clean up 
        """
        self._writer.endDocument()
        return

感谢您的帮助。

【问题讨论】：

标签： python xml jython dtd

【解决方案1】：

您可以继承 XMLGenerator 并添加一个 write() 方法。这是一个例子：

import sys
from xml.sax.saxutils import XMLGenerator

class MyXMLGenerator(XMLGenerator):
    def __init__(self, out=sys.stdout, encoding="UTF-8"):
        XMLGenerator.__init__(self, out, encoding)
        self.out = out

    def write (self,s):
        self.out.write(s)

def writexml(out):
    xmlwriter = MyXMLGenerator(out)
    xmlwriter.startDocument()
    xmlwriter.write("<!DOCTYPE test SYSTEM 'test.dtd'>\n")
    xmlwriter.startElement('test', {"a": "1"})
    xmlwriter.characters('abc123')
    xmlwriter.endElement('test')
    xmlwriter.endDocument()

if __name__ == '__main__':
    writexml(out=open("out.xml", "w"))

out.xml 中的结果输出：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE test SYSTEM 'test.dtd'>
<test a="1">abc123</test>

【讨论】：