Node-RED中使用json节点解析JSON数据

刺骨的言语ヽ痛彻心扉 2023-09-30 13:06 0阅读 0赞

## 场景 ##

Node-RED简介与Windows上安装、启动和运行示例：

[Node-RED简介与Windows上安装、启动和运行示例\_霸道流氓气质的博客-CSDN博客][Node-RED_Windows_-CSDN]

Node-RED怎样导出导入流程为json文件：

[Node-RED怎样导出导入流程为json文件\_霸道流氓气质的博客-CSDN博客][Node-RED_json_-CSDN]

json示例数据如下

[{"title": "ASP.NET網頁程式設計", "author": "陳會安", "category": "Web", "pubdate": "06/2015", "id": "W101"}, {"title": "PHP網頁程式設計", "author": "陳會安", "category": "Web", "pubdate": "07/2015", "id": "W102"}, {"title": "Java程式設計", "author": "陳會安", "category": "Programming", "pubdate": "11/2015", "id": "P102"}, {"title": "Android程式設計", "author": "陳會安", "category": "Mobile", "pubdate": "07/2015", "id": "M102"}]

![d466ca81ca0c1a39c08c5a051dd6f3c3.png][]

怎样解析该json数据并获取指定对象的属性。

注：

博客：  
[霸道流氓气质的博客\_CSDN博客-C\#,架构之路,SpringBoot领域博主][CSDN_-C_SpringBoot]  
关注公众号  
霸道的程序猿  
获取编程相关电子书、教程推送与免费下载。

## 实现 ##

1、使用http request组件请求json数据，请求地址

[https://fchart.github.io/books.json][https_fchart.github.io_books.json]

![98290c60cd5339e9e45ed6f78373ed59.png][]

2、使用json解析组件解析，并选择JSON字符串与对象互转

![96bb015dc838907ec9f5797f367e39bf.png][]

3、输出选择第一个对象的title属性

![23f6ad175bb8ffdb8a168a0b4adb9bd9.png][]

4、效果

![ba7930d1da54076da5957ff8ab571e28.png][]

5、json数据

[
        {
            "id": "f4a4d8eab7935bc8",
            "type": "tab",
            "label": "流程 3",
            "disabled": false,
            "info": "",
            "env": []
        },
        {
            "id": "c428312d1f6165d1",
            "type": "mqtt-broker",
            "name": "mqtt",
            "broker": "127.0.0.1",
            "port": "1883",
            "clientid": "",
            "autoConnect": true,
            "usetls": false,
            "protocolVersion": "4",
            "keepalive": "60",
            "cleansession": true,
            "birthTopic": "",
            "birthQos": "0",
            "birthPayload": "",
            "birthMsg": {},
            "closeTopic": "",
            "closeQos": "0",
            "closePayload": "",
            "closeMsg": {},
            "willTopic": "",
            "willQos": "0",
            "willPayload": "",
            "willMsg": {},
            "sessionExpiry": ""
        },
        {
            "id": "51eee50b4ec9422f",
            "type": "ui_group",
            "name": "dashboardDemo",
            "tab": "29ae4c620f43ee0d",
            "order": 1,
            "disp": true,
            "width": "6",
            "collapse": false,
            "className": ""
        },
        {
            "id": "29ae4c620f43ee0d",
            "type": "ui_tab",
            "name": "Home",
            "icon": "dashboard",
            "disabled": false,
            "hidden": false
        },
        {
            "id": "a506c767a5c1edbd",
            "type": "ui_base",
            "theme": {
                "name": "theme-light",
                "lightTheme": {
                    "default": "#0094CE",
                    "baseColor": "#0094CE",
                    "baseFont": "-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen-Sans,Ubuntu,Cantarell,Helvetica Neue,sans-serif",
                    "edited": true,
                    "reset": false
                },
                "darkTheme": {
                    "default": "#097479",
                    "baseColor": "#097479",
                    "baseFont": "-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen-Sans,Ubuntu,Cantarell,Helvetica Neue,sans-serif",
                    "edited": false
                },
                "customTheme": {
                    "name": "Untitled Theme 1",
                    "default": "#4B7930",
                    "baseColor": "#4B7930",
                    "baseFont": "-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen-Sans,Ubuntu,Cantarell,Helvetica Neue,sans-serif"
                },
                "themeState": {
                    "base-color": {
                        "default": "#0094CE",
                        "value": "#0094CE",
                        "edited": false
                    },
                    "page-titlebar-backgroundColor": {
                        "value": "#0094CE",
                        "edited": false
                    },
                    "page-backgroundColor": {
                        "value": "#fafafa",
                        "edited": false
                    },
                    "page-sidebar-backgroundColor": {
                        "value": "#ffffff",
                        "edited": false
                    },
                    "group-textColor": {
                        "value": "#1bbfff",
                        "edited": false
                    },
                    "group-borderColor": {
                        "value": "#ffffff",
                        "edited": false
                    },
                    "group-backgroundColor": {
                        "value": "#ffffff",
                        "edited": false
                    },
                    "widget-textColor": {
                        "value": "#111111",
                        "edited": false
                    },
                    "widget-backgroundColor": {
                        "value": "#0094ce",
                        "edited": false
                    },
                    "widget-borderColor": {
                        "value": "#ffffff",
                        "edited": false
                    },
                    "base-font": {
                        "value": "-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen-Sans,Ubuntu,Cantarell,Helvetica Neue,sans-serif"
                    }
                },
                "angularTheme": {
                    "primary": "indigo",
                    "accents": "blue",
                    "warn": "red",
                    "background": "grey",
                    "palette": "light"
                }
            },
            "site": {
                "name": "Node-RED Dashboard",
                "hideToolbar": "false",
                "allowSwipe": "false",
                "lockMenu": "false",
                "allowTempTheme": "true",
                "dateFormat": "DD/MM/YYYY",
                "sizes": {
                    "sx": 48,
                    "sy": 48,
                    "gx": 6,
                    "gy": 6,
                    "cx": 6,
                    "cy": 6,
                    "px": 0,
                    "py": 0
                }
            }
        },
        {
            "id": "248cbbb0.18e794",
            "type": "ui_group",
            "name": "MyGroup",
            "tab": "3f79c420.cfc1bc",
            "order": 1,
            "disp": true,
            "width": "6",
            "collapse": false
        },
        {
            "id": "3f79c420.cfc1bc",
            "type": "ui_tab",
            "name": "Home",
            "icon": "dashboard",
            "disabled": false,
            "hidden": false
        },
        {
            "id": "a0954be5.a7f7e8",
            "type": "ui_group",
            "name": "MyInput",
            "tab": "3f79c420.cfc1bc",
            "order": 2,
            "disp": true,
            "width": "6",
            "collapse": false
        },
        {
            "id": "ffb7767d.5ec0c8",
            "type": "http request",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "method": "GET",
            "ret": "txt",
            "paytoqs": "ignore",
            "url": "https://fchart.github.io/books.json",
            "tls": "",
            "persist": false,
            "proxy": "",
            "authType": "",
            "senderr": false,
            "x": 360,
            "y": 180,
            "wires": [
                [
                    "77c6d060.4df97"
                ]
            ]
        },
        {
            "id": "a7936a3e.034b98",
            "type": "inject",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "repeat": "",
            "crontab": "",
            "once": false,
            "topic": "",
            "payload": "",
            "payloadType": "date",
            "x": 210,
            "y": 180,
            "wires": [
                [
                    "ffb7767d.5ec0c8"
                ]
            ]
        },
        {
            "id": "77c6d060.4df97",
            "type": "json",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "property": "payload",
            "action": "",
            "pretty": false,
            "x": 510,
            "y": 180,
            "wires": [
                [
                    "80b292a2.4dcf5",
                    "5f300589.d8d4fc"
                ]
            ]
        },
        {
            "id": "80b292a2.4dcf5",
            "type": "debug",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "active": true,
            "tosidebar": true,
            "console": false,
            "tostatus": false,
            "complete": "payload[0].title",
            "targetType": "msg",
            "statusVal": "",
            "statusType": "auto",
            "x": 710,
            "y": 200,
            "wires": []
        },
        {
            "id": "5f300589.d8d4fc",
            "type": "debug",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "active": true,
            "tosidebar": true,
            "console": false,
            "tostatus": false,
            "complete": "payload[0].id",
            "targetType": "msg",
            "statusVal": "",
            "statusType": "auto",
            "x": 710,
            "y": 140,
            "wires": []
        }
    ]

[Node-RED_Windows_-CSDN]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/121884766
[Node-RED_json_-CSDN]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/124130985
[d466ca81ca0c1a39c08c5a051dd6f3c3.png]: https://img-blog.csdnimg.cn/img_convert/d466ca81ca0c1a39c08c5a051dd6f3c3.png
[CSDN_-C_SpringBoot]: https://blog.csdn.net/badao_liumang_qizhi
[https_fchart.github.io_books.json]: https://fchart.github.io/books.json
[98290c60cd5339e9e45ed6f78373ed59.png]: https://img-blog.csdnimg.cn/img_convert/98290c60cd5339e9e45ed6f78373ed59.png
[96bb015dc838907ec9f5797f367e39bf.png]: https://img-blog.csdnimg.cn/img_convert/96bb015dc838907ec9f5797f367e39bf.png
[23f6ad175bb8ffdb8a168a0b4adb9bd9.png]: https://img-blog.csdnimg.cn/img_convert/23f6ad175bb8ffdb8a168a0b4adb9bd9.png
[ba7930d1da54076da5957ff8ab571e28.png]: https://img-blog.csdnimg.cn/img_convert/ba7930d1da54076da5957ff8ab571e28.png