Question

我是Firebase 3.0和编码新手，无法检索特定节点ID并写入其中。在下面的示例中，我刚刚创建了用户，现在想要将该用户添加到特定设施。我如何搜索名为＆＃34; Upper Paw＆＃34;然后将用户添加到其中

当前：

application  
    -facilities  
        -KRFGFn7TzKR8D0bMLW  
            facName: "Upper Paw"  
            facPhone: "5122223333"  
    -users  
        -MqrvHRBTRcPzrvAOdkklBzeFW7E2  
            firstName: "Ronnie"  
            lastName: "Last"

目标：

application   
    -facilities  
        -KRFGFn7TzKR8D0bMLW  
            facName: "Upper Paw"  
            facPhone: "5122223333"
            users:   
                -MqrvHRBTRcPzrvAOdkklBzeFW7E2  
                    firstName: "Ronnie"  
                    lastName: "Last"  
    -users  

        -MqrvHRBTRcPzrvAOdkklBzeFW7E2  
            firstName: "Ronnie"  
            lastName: "Last"

这是我的代码来提取设施中的值（它提取所有设施数据，但不确定如何查询和找到上爪的设施并向其写入其他数据：

let facRef = rootRef.child("facilities")

            facRef.observeSingleEventOfType(.Value, withBlock: { (snapshot) in

             print(snapshot.value)

Answer 1

let facRef = rootRef.child("facilities")

let faqQuery = facRef. queryOrderedByChild("facName"). queryEqualToValue("Upper Paw")

faqQuery.observeSingleEventOfType(.ChildAdded, withBlock: { (snapshot) in

    print(snapshot.value)

有关详细信息，请参阅Firebase documentation on querying。

要了解如何修改数据，请参阅Firebase documentation on saving data。基于你的块可能是：

 snapshot.ref.child("facMember").setValue("Ronnie L")

Answer 2

    let ref = FIRDatabase.database().reference(fromURL: "DATABASE_URL")
    let usersRef = ref.child("users")
    usersRef.queryOrdered(byChild: "facName").queryEqual(toValue: "Upper Paw").observeSingleEvent(of: .value, with: { (snapshot) in
    print(snapshot)
   })

如何检索Firebase 3.0项/ Swift的键值

2 个答案: