JavaScript Day09 - 物件、阵列与 JSON

物件与阵列组合

前一天有提到，物件内也可以放物件与阵列，而阵列内也是，除了字串与数字外，也可以加入阵列与物件
读取原则
- 阵列：第 n-1 个(因为从 0 开始)，arr[n-1]
- 物件：属性的名称，obj.keyName 或 obj["keyName"]

查有几笔： data.length
查第 1 笔的总运量：data[0].总运量 或 data[0]["总运量"]，会得到 275360
(正常应该用英文命名比较好)

let data = [
    {
        "年": 107,
        "月": 1,
        "总运量": 275360,
        "日均运量": 8883,
        "假日均运量": 15132,
        "月台上刷卡日均笔数": 1734.2,
        "车上刷卡日均笔数": 5495.9,
        "售票机日均笔数": 1516.8,
        "补票日均笔数": 9.4,
        "团体票日均笔数": 126.3
    },
    // 略
    {
        "年": 110,
        "月": 8,
        "总运量": 141994,
        "日均运量": 4580,
        "假日均运量": 5851,
        "月台上刷卡日均笔数": 1407,
        "车上刷卡日均笔数": 2991.5,
        "售票机日均笔数": 175.5,
        "人工售票日均笔数": 6.4,
        "备注": ""
      }
]

JSON

JSON 的相关说明可以参考：Day19 - JSON
就是物件与阵列的混合，属性名称会加入 " "

资料连结：高雄YouBike2.0公共自行车租赁站即时资讯

可以发现主要资料都放在 jsonData.data.retVal 内

想要查站点数量：jsonData.data.retVal.length
查第 1 笔的区域位置：jsonData.data.retVal[0].sarea // 凤山区

let jsonData = {
    "contentType": "application/json",
    "isImage": false,
    "data": {
        "retCode": 1,
        "updated_at": "2021-09-24 22:09:15",
        "retVal": [
            {
                "scity": "高雄市",
                "scityen": "Kaohsiung City",
                "sna": "YouBike2.0_山仔顶沟滞洪池",
                "sarea": "凤山区",
                "ar": "埤山路/埤北路305巷口东侧",
                "snaen": "YouBike2.0_Shanziding Detention Ponds",
                "sareaen": "Fongshan Dist",
                "aren": "Pibei Rd./Lane237 Pibei Rd. (Northeast)",
                "sno": "501206115",
                "tot": "15",
                "sbi": "6",
                "mday": "20210924210116",
                "lat": "22.63428",
                "lng": "120.37921",
                "bemp": "9",
                "act": 1
            },
            // 略
        ]
    },
    "id": "cbdb9a4c-40ca-4b56-ae9d-298e14c9498f",
    "message": null,
    "success": true
}