Retrieve data of child of unknown parent ID - Firebase

Question

I have a Firebase database like shown in the image.

I want to get all the data highlighted in GREEN. But I don't know keys highlighted in RED.

What should be the JavaScript Code for this?

Thanks in advance.

Answer 1

这会记录所有电话号码：

var usersRef = firebase.database().ref("users");
usersRef.on("child_added", function(snapshot) {
    console.log(snapshot.child("phoneno").val());
});

请注意，Firebase documentation和Codelab涵盖了此内容以及更多内容。我强烈建议您花一些时间在这些上，以便更熟悉Firebase。

如果您想打印所有电话号码一次，可以使用以下方式打印：

var usersRef = firebase.database().ref("users");
usersRef.once("value", function(snapshot) {
  snapshot.forEach(function(userSnapshot) {
    console.log(userSnapshot.child("phoneno").val());
  });
});

listening for value events on a collection of data的文档中介绍了这一具体案例。