我如何从React读取和写入Firestore中的地图值?

我在firestore中有一个数据库字段,其中有一个这样的地图:

坐标:{_ 01:“铜”,_02:“金”,_03:“铁”}

我在Firestore管理面板中看到此数据库,如下所示: pic

当我尝试使用以下代码列出项目

data.cordinates.map((item,i)=>
                  console.log(i+" - "+item)
                );

我收到:

Unhandled Rejection (TypeError): data.cordinates.map is not a function

读/写这种地图的正确方法是什么?

btw console.log(data.cordinates)给我这样的输出:

{_01: "copper",_02: "gold",_03: "iron",_04: "",_05: "", …}
_01: "copper"
_02: "gold"
_03: "iron"
_04: ""
_05: ""
_06: ""
_07: ""
_08: ""
_10: ""
_11: ""
_12: ""
_13: ""
_14: ""
_15: ""
_16: ""
_17: ""
_18: ""
_20: ""
_21: ""
_22: ""
_23: ""
_24: ""
_25: ""
_26: ""
_27: ""
_28: ""
_30: ""
_31: ""
_32: ""
_33: ""
_34: ""
_35: ""
_36: ""
_37: ""
_38: ""
_40: ""
_41: ""
_42: ""
_43: ""
_44: ""
_45: ""
_46: ""
_47: ""
_48: ""

是的,总共有48个元素

非常感谢您的帮助。

q178455231 回答:我如何从React读取和写入Firestore中的地图值?

map更改为forin

这是示例代码:

const cord = data.cordinates || {} // to handle undefined `data.cordinates` case
for(let i in cord){
   if(cord.hasOwnProperty(i)){
     const item = cord[i];
     console.log(i+" - "+item);
     // do your other stuff here
   }
}
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