Node-RED中将CSV数据写入txt文件并从文件中读取解析数据

超、凢脫俗 2023-09-30 13:07 168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\_nodered windows][Node-RED_Windows_-CSDN_nodered windows]

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\_怎么导出json文件][Node-RED_json_-CSDN_json]

CSV的内容是使用纯文字方式表示的表格资料，第一行是表格的标题，每一列用,隔开。

例如：

Name,height,weight  
Joe,170,70  
Mary,160,49

怎样将数据存储到txt文件中，需要时从文件中读取并解析获取数据。

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、页面布局

![3b7b9f1f62f811941954dbacd913308c.png][]

2、template节点，输入csv资料

![5b44e7fdc8e54d51144d7eef3a6169d1.png][]

3、file节点，将csv资料用utf-8编码写入D://file.txt

![fc6359bf80ecc491bbb7d859c3e2a203.png][]

4、file in节点，读取file.txt，输出utf-8的一个字符

![a193733997f14c26309f1885e7fd8a81.png][]

5、csv节点，剖析csv资料，输入列名，分隔符是逗号，因为第一列是标题列，所以在输入时忽略第一行

输出时选择每行一条信息

![71fd46e6de48403418171459aa07edb9.png][]

6、解析效果

![fb1a55429c5bff31672f841bf9b8204f.png][]

7、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": "508bd6f8398ab80f",
            "type": "ui_group",
            "name": "OpenWeatherMap",
            "tab": "3f79c420.cfc1bc",
            "order": 3,
            "disp": true,
            "width": "6",
            "collapse": false
        },
        {
            "id": "8824dea1.83e31",
            "type": "websocket-client",
            "path": "ws://localhost:9898/",
            "tls": "",
            "wholemsg": "false"
        },
        {
            "id": "f9c23ff5.026e",
            "type": "file",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "filename": "D://file.txt",
            "appendNewline": true,
            "createDir": false,
            "overwriteFile": "true",
            "encoding": "utf8",
            "x": 480,
            "y": 180,
            "wires": [
                []
            ]
        },
        {
            "id": "2ebfe992.fdc746",
            "type": "inject",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "repeat": "",
            "crontab": "",
            "once": false,
            "onceDelay": 0.1,
            "topic": "",
            "payload": "",
            "payloadType": "date",
            "x": 190,
            "y": 240,
            "wires": [
                [
                    "cfaafb8.012a108"
                ]
            ]
        },
        {
            "id": "cfaafb8.012a108",
            "type": "file in",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "filename": "D://file.txt",
            "format": "utf8",
            "chunk": false,
            "sendError": false,
            "encoding": "utf8",
            "allProps": false,
            "x": 340,
            "y": 240,
            "wires": [
                [
                    "ee4f2b44.0fc328"
                ]
            ]
        },
        {
            "id": "32435220.d9c6ee",
            "type": "debug",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "active": true,
            "tosidebar": true,
            "console": false,
            "tostatus": false,
            "complete": "payload.weight",
            "targetType": "msg",
            "statusVal": "",
            "statusType": "auto",
            "x": 680,
            "y": 280,
            "wires": []
        },
        {
            "id": "ee4f2b44.0fc328",
            "type": "csv",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "sep": ",",
            "hdrin": "",
            "hdrout": "none",
            "multi": "one",
            "ret": "\\n",
            "temp": "name,height,weight",
            "skip": "1",
            "strings": true,
            "include_empty_strings": "",
            "include_null_values": "",
            "x": 470,
            "y": 240,
            "wires": [
                [
                    "f250620f.1071d",
                    "d9c16f6a.a9d4b",
                    "32435220.d9c6ee"
                ]
            ]
        },
        {
            "id": "f250620f.1071d",
            "type": "debug",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "active": true,
            "tosidebar": true,
            "console": false,
            "tostatus": false,
            "complete": "payload.name",
            "targetType": "msg",
            "statusVal": "",
            "statusType": "auto",
            "x": 670,
            "y": 200,
            "wires": []
        },
        {
            "id": "d9c16f6a.a9d4b",
            "type": "debug",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "active": true,
            "tosidebar": true,
            "console": false,
            "tostatus": false,
            "complete": "payload.height",
            "targetType": "msg",
            "statusVal": "",
            "statusType": "auto",
            "x": 670,
            "y": 240,
            "wires": []
        },
        {
            "id": "277f6cb6.89e434",
            "type": "template",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "field": "payload",
            "fieldType": "msg",
            "format": "handlebars",
            "syntax": "mustache",
            "template": "Name,height,weight\nJoe,170,70\nMary,160,49",
            "output": "str",
            "x": 330,
            "y": 180,
            "wires": [
                [
                    "f9c23ff5.026e"
                ]
            ]
        },
        {
            "id": "f22a93b5.26844",
            "type": "inject",
            "z": "f4a4d8eab7935bc8",
            "name": "",
            "props": [
                {
                    "p": "payload"
                },
                {
                    "p": "topic",
                    "vt": "str"
                }
            ],
            "repeat": "",
            "crontab": "",
            "once": false,
            "onceDelay": 0.1,
            "topic": "",
            "payloadType": "date",
            "x": 190,
            "y": 180,
            "wires": [
                [
                    "277f6cb6.89e434"
                ]
            ]
        }
    ]

[Node-RED_Windows_-CSDN_nodered windows]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/121884766
[Node-RED_json_-CSDN_json]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/124130985
[CSDN_-C_SpringBoot]: https://blog.csdn.net/badao_liumang_qizhi
[3b7b9f1f62f811941954dbacd913308c.png]: https://img-blog.csdnimg.cn/img_convert/3b7b9f1f62f811941954dbacd913308c.png
[5b44e7fdc8e54d51144d7eef3a6169d1.png]: https://img-blog.csdnimg.cn/img_convert/5b44e7fdc8e54d51144d7eef3a6169d1.png
[fc6359bf80ecc491bbb7d859c3e2a203.png]: https://img-blog.csdnimg.cn/img_convert/fc6359bf80ecc491bbb7d859c3e2a203.png
[a193733997f14c26309f1885e7fd8a81.png]: https://img-blog.csdnimg.cn/img_convert/a193733997f14c26309f1885e7fd8a81.png
[71fd46e6de48403418171459aa07edb9.png]: https://img-blog.csdnimg.cn/img_convert/71fd46e6de48403418171459aa07edb9.png
[fb1a55429c5bff31672f841bf9b8204f.png]: https://img-blog.csdnimg.cn/img_convert/fb1a55429c5bff31672f841bf9b8204f.png