- 1. 前言
- 2. node-red中jsonDas Format的转换
- 3. node-red中处理 xmlDas Format的Daten
前言
在使用node-red处理各种业务Szene时，我们时常会遇zu各种各样的Datenformate，最Häufig的是jsonDatenformate，其次还有xml，yaml，以及csvDas Format的Datenformate。这些都是需要我们对其Datenformate有一点Analyse和转化的能力，今天这篇Artikel我就来教大家如何处理json 和 xmlDatenformate。
node-red中jsonDas Format的转换
在node-red中处理jsonDatenformate是最简单的。最主要的原因是node-red本身就是使用javascript语言来编写的。而javascript中am häufigsten verwendet的就是jsonDatenformate。声明一个jsonDatenformate很简单。
# json Daten的声明
const person = {name: 'fizzz', age:12}
# 打印Daten
console.log(person.name)
# 重新Zuweisung
person.name = 'tom'
json Datenformate的Operationen就是这样的简单。
下面是一个json转换的流，大家可以从这个流中体验的对jsonDaten的Operationen。
[{"id":"634256b7.2d6818","type":"inject","z":"64133d39.bb0394","name":"JSON String","topic":"","payload":"{"a":1}","payloadType":"str","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":110,"y":80,"wires":[["a2fe0fc8.095e1"]]},{"id":"a2fe0fc8.095e1","type":"json","z":"64133d39.bb0394","name":"","property":"payload","action":"","pretty":false,"x":270,"y":80,"wires":[["9a4ce2b8.47698"]]},{"id":"9a4ce2b8.47698","type":"debug","z":"64133d39.bb0394","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":430,"y":80,"wires":[]},{"id":"80032e2.7c92cd","type":"inject","z":"64133d39.bb0394","name":"Object","topic":"","payload":"{"a":1}","payloadType":"json","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":90,"y":120,"wires":[["cd40a0f4.4f5ac"]]},{"id":"cd40a0f4.4f5ac","type":"json","z":"64133d39.bb0394","name":"","property":"payload","action":"","pretty":false,"x":270,"y":120,"wires":[["478b4106.4fd7c"]]},{"id":"478b4106.4fd7c","type":"debug","z":"64133d39.bb0394","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":430,"y":120,"wires":[]}]
效果图如下：
json Daten的处理主要是借助来json核心节点，它可以将Charaktere串与jsonDaten互转。 非常方便。如果转换失败就会报错。
json 节点的详细配置如下：
输入Parameter：payload：object | Charaktere串
JavaScript对象或JSONCharaktere串。schema：object
可选的JSON Schema对象用于验证Wirksam负载。在将msgSenden Siezu下一个节点之前，将Löschen该属性。
输出Parameter：payload：object | Charaktere串
如果输入是JSONCharaktere串，它将尝试将其Analyse为JavaScript对象。
如果输入是JavaScript对象，它将创建一个JSONCharaktere串。并可以Auswahl对此JSONCharaktere串进行整形。schema：Error数组
如果JSON模式验证失败，则catch节点将具有包含Fehler.数组的schemaError属性。
node-red中处理 xmlDas Format的Daten
在ndoe-red中处理xml的Daten，主要Szene是 jsonDaten转换为xmlDaten，或者xmlDas Format的Daten转换为jsonDatenformate。Von denen主要借助的是xml核心节点，其底层是使用了xml2json这个库。
xml这个节点的需要的输入有二个Parameter
payload ： object | Charaktere串
设置为JavaScript对象或XMLCharaktere串。
options：object
可以将选项传递给内部使用的XML转换库。请参见 xml2jsDokumentation 来获取mehr.信息。
输出Ergebnis是payload : object | Charaktere串
如果输入是Charaktere串，它将尝试将其Analyse为XML并创建一个JavaScript对象。
如果输入是JavaScript对象，它将尝试构建XMLCharaktere串。
另外在XML和对象之间进行转换时，默认情况下XML属性会添加zu名为$的属性中。将Text内容添加zu名为_的属性中。这些属性Name可以在节点设置中更改。
下面是一个例子，大家可以从这个例子感受zunode-red对xmlDaten与jsonDatenformate的转换
[{"id":"1b546d47.9474e3","type":"inject","z":"64133d39.bb0394","name":"XML String","topic":"","payload":"{"a":1}","payloadType":"str","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":100,"y":260,"wires":[["d72b2bfd.77d068"]]},{"id":"1adf407d.6c4fe","type":"debug","z":"64133d39.bb0394","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":590,"y":260,"wires":[]},{"id":"46638890.8ae758","type":"inject","z":"64133d39.bb0394","name":"Object","topic":"","payload":"{"note":{"$":{"priority":"high"},"to":["Nick"],"from":["Dave"],"heading":["Reminder"],"body":["Update the website"]}}","payloadType":"json","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":90,"y":300,"wires":[["dae1d291.de0d2"]]},{"id":"6fefca67.3669e4","type":"debug","z":"64133d39.bb0394","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":430,"y":300,"wires":[]},{"id":"d72b2bfd.77d068","type":"template","z":"64133d39.bb0394","name":"","field":"payload","fieldType":"msg","format":"text","syntax":"plain","template":"<note priority="high">n <to>Nick</to>n <from>Dave</from>n <heading>Reminder</heading>n <body>Update the website</body>n</note>","output":"str","x":280,"y":260,"wires":[["1746464a.87aa4a"]]},{"id":"1746464a.87aa4a","type":"xml","z":"64133d39.bb0394","name":"","property":"payload","attr":"","chr":"","x":430,"y":260,"wires":[["1adf407d.6c4fe"]]},{"id":"dae1d291.de0d2","type":"xml","z":"64133d39.bb0394","name":"","property":"payload","attr":"","chr":"","x":250,"y":300,"wires":[["6fefca67.3669e4"]]}]
流示意图
Antwort veröffentlichen