如何查询由json-to-xml生成的XML文档节点？

可以使用XPath表达式来查询XML文档节点。具体步骤如下：

1. 首先，需要使用json-to-xml库将JSON转换为XML。以下是示例JSON数据和转换为XML的示例代码：

const json = { "employees": { "employee": [ { "firstName": "John", "lastName": "Doe" }, { "firstName": "Anna", "lastName": "Smith" }, { "firstName": "Peter", "lastName": "Jones" } ] } };

const { xml } = convert.js2xml(json, { compact: true });

console.log(xml);

输出的XML如下所示：

<employees> <employee> <firstName>John</firstName> <lastName>Doe</lastName> </employee> <employee> <firstName>Anna</firstName> <lastName>Smith</lastName> </employee> <employee> <firstName>Peter</firstName> <lastName>Jones</lastName> </employee> </employees>

2. 然后，可以使用XPath表达式来查询XML文档节点。以下是示例代码：

const xpath = require('xpath'); const dom = require('xmldom').DOMParser;

const doc = new dom().parseFromString(xml);

const nodes = xpath.select("//employees/employee/firstName", doc);

console.log(nodes);

输出结果为：

[ { nodeName: 'firstName', localName: 'firstName', namespaceURI: null, prefix: null, context: {}, nodeValue: 'John' }, { nodeName: 'firstName', localName: 'firstName', namespaceURI: null, prefix: null, context: {}, nodeValue: 'Anna' }, { nodeName: 'firstName', localName: 'firstName', namespaceURI: null, prefix: null, context: {}, nodeValue: 'Peter' } ]

上面的代码使用XPath表达式'//employees/employee/firstName”查询所有employee节点下的firstName节点，并返回查询结果。

这就是如何使用XPath表达式查询由json-to-xml生成的XML文档节点的方法。