firebase实时数据库在使用angularfire 2进行筛选后更新条目
实时数据库中的数据结构如下:firebase实时数据库在使用angularfire 2进行筛选后更新条目,firebase,firebase-realtime-database,angularfire2,Firebase,Firebase Realtime Database,Angularfire2,实时数据库中的数据结构如下: "orders" : { "-LM5p4tl7Og_PMJOspZ-" : { "customer" : { "_name" : "Vik Kumar", "_uid" : "oSEYj0zrkhPCk9r7uwyOOkHcqe53" }, "order" : { "_orderNumber" : "VikKumar-26954", "_orderStatus
"orders" : {
"-LM5p4tl7Og_PMJOspZ-" : {
"customer" : {
"_name" : "Vik Kumar",
"_uid" : "oSEYj0zrkhPCk9r7uwyOOkHcqe53"
},
"order" : {
"_orderNumber" : "VikKumar-26954",
"_orderStatus" : "Pending",
"_orderTotal" : 500,
}
},
"-LM5s1wRCvqWA1vsZONy" : {
"customer" : {
"_name" : "Vik Kumar",
"_uid" : "oSEYj0zrkhPCk9r7uwyOOkHcqe53"
},
"order" : {
"_orderNumber" : "VikKumar-11423",
"_orderStatus" : "Pending",
"_orderTotal" : 500,
}
},
"-LM5sOHzjLeqFGFleMxq" : {
"customer" : {
"_name" : "Vik Kumar",
"_uid" : "oSEYj0zrkhPCk9r7uwyOOkHcqe53"
},
"order" : {
"_orderNumber" : "VikKumar-63772",
"_orderStatus" : "Pending",
"_orderTotal" : 500,
}
}
}
我在我的ionic应用程序中使用angularfire2,并过滤以下几个订单:
getPendingOrders(dateStr:string){
return new Promise((resolve, reject) =>
{
this.db.list('orders',
ref => ref.orderByChild("order/_date").equalTo(dateStr)
).valueChanges().subscribe(
res => {
resolve(res)
},
err => {
console.log(err)
reject(err)
}
)
})
}
上面的查询给了我如下的回答
[{"customer": {}, "order": {}}, {"customer": {}, "order": {}}]
我可以在UI中呈现它,我希望最终用户能够更新属性“\u orderStatus”的值。问题在于我查询数据的方式,我丢失了识别特定对象以更新它的键。请告知好的,不确定这是否有帮助,我认为您已迁移到使用AngularFire 5.0。调用.valueChanges()将返回一个不带任何元数据的可观察对象(例如项键),您需要改用.snapshotChanges()调用:
this.db.list(...)
.snapshotChanges()
.map(changes => {
return changes.map(change => ({key: change.payload.key, ...change.payload.val()}));
})
.subscribe(...)
这一次有什么帮助吗?