python - 如何从 XPath 查询中的先前属性值中提取嵌入的属性值？

Question

我正在尝试从以下 html 部分的 onclick 属性中“选择”链接

<span onclick="Javascript:document.quickFindForm.action='/blah_blah'" 
 class="specialLinkType"><img src="blah"></span>

但不能比下面的 XPath 更进一步

//span[@class="specialLinkType"]/@onclick

只返回

Javascript:document.quickFindForm.action

关于如何使用 XPath 在 quickFindForm.action 中选择该链接有什么想法吗？

Answer 1

我在 Java 应用程序中尝试了 XPath，它工作正常:

    import java.io.IOException;
    import java.io.StringReader;

    import javax.xml.parsers.DocumentBuilder;
    import javax.xml.parsers.DocumentBuilderFactory;
    import javax.xml.parsers.ParserConfigurationException;
    import javax.xml.xpath.XPath;
    import javax.xml.xpath.XPathExpression;
    import javax.xml.xpath.XPathFactory;

    import org.w3c.dom.Document;
    import org.xml.sax.InputSource;
    import org.xml.sax.SAXException;

    public class Teste {

        public static void main(String[] args) throws Exception {
            Document doc = stringToDom("<span onclick=\"Javascript:document.quickFindForm.action='/blah_blah'\" class=\"specialLinkType\"><img src=\"blah\"/></span>");
            XPath newXPath = XPathFactory.newInstance().newXPath();
            XPathExpression xpathExpr = newXPath.compile("//span[@class=\"specialLinkType\"]/@onclick");
            String result = xpathExpr.evaluate(doc);
            System.out.println(result);

        }

        public static Document stringToDom(String xmlSource) throws SAXException, ParserConfigurationException, IOException {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            return builder.parse(new InputSource(new StringReader(xmlSource)));
        }
    }

结果:

Javascript:document.quickFindForm.action='/blah_blah'