場景

Node-RED簡介與Windows上安裝、啟動和執行示例：

https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/121884766

Node-RED怎樣匯出匯入流程為json檔案：

https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/124130985

Node-RED安裝圖形化節點dashboard實現訂閱mqtt主題並在儀表盤中顯示溫度：

https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/121992760

在上面的基礎上怎樣使用node-random隨機數節點，並構造出變化的模擬資料

在折線圖中顯示。

注：

部落格：
https://blog.csdn.net/badao_liumang_qizhi
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實現

1、選單-節點管理-搜尋node-red-node-random隨機數節點，來產生隨機數。

然後就可以在面板中找到random元件

編輯random節點從1到100

2、拖拽chart元件並編輯折線圖屬性

設定inject節點每隔兩秒執行

3、json資料

[
    {
        "id": "bd92edab3c781ab4
 
",
        "type": "inject",
        "z": "f4a4d8eab7935bc8",
        "name": "",
        "props": [
            {
                "p": "payload"
            },
            {
                "p": "topic",
                "vt": "str"
            }
        ],
        "repeat": "2",
        "crontab": ""
 
,
        "once": false,
        "onceDelay": 0.1,
        "topic": "",
        "payloadType": "date",
        "x": 220,
        "y": 180,
        "wires": [
            [
                "97002e0a588d91d2"
            ]
        ]
    },
    {
        "id": "3ecb265fb81d22fc",
        "type": "debug",
        "z": "f4a4d8eab7935bc8",
        "name": "",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "false",
        "x": 590,
        "y": 180,
        "wires": []
    },
    {
        "id": "97002e0a588d91d2",
        "type": "random",
        "z": "f4a4d8eab7935bc8",
        "name": "",
        "low": 1,
        "high": "100",
        "inte": "true",
        "property": "payload",
        "x": 400,
        "y": 180,
        "wires": [
            [
                "3ecb265fb81d22fc",
                "6a376c712f33f004"
            ]
        ]
    },
    {
        "id": "6a376c712f33f004",
        "type": "ui_chart",
        "z": "f4a4d8eab7935bc8",
        "name": "",
        "group": "248cbbb0.18e794",
        "order": 1,
        "width": 0,
        "height": 0,
        "label": "折線圖",
        "chartType": "line",
        "legend": "false",
        "xformat": "HH:mm:ss",
        "interpolate": "linear",
        "nodata": "",
        "dot": false,
        "ymin": "",
        "ymax": "",
        "removeOlder": 1,
        "removeOlderPoints": "20",
        "removeOlderUnit": "3600",
        "cutout": 0,
        "useOneColor": false,
        "useUTC": false,
        "colors": [
            "#1f77b4",
            "#aec7e8",
            "#ff7f0e",
            "#2ca02c",
            "#98df8a",
            "#d62728",
            "#ff9896",
            "#9467bd",
            "#c5b0d5"
        ],
        "outputs": 1,
        "useDifferentColor": false,
        "className": "",
        "x": 570,
        "y": 260,
        "wires": [
            []
        ]
    },
    {
        "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
    }
]