获取自动生成的 ID - Firebase

Question

I'm trying to retrieve the id of the element that I inserted in the database with .key . However, it returns the user value instead of the auto-generated id.

How can I get the auto-generated id ?

var mainText = document.getElementById("main-text");
var emailText = document.getElementById("emailtxt");
var prenom = document.getElementById("prenomtxt");
var submitBtn = document.getElementById("submitBtn");
var heading = document.getElementById("heading");



var firebaseHeadingref = firebase.database().ref().child("titre");
firebaseHeadingref.on('value', function(datasnapchot){
  heading.innerText = datasnapchot.val();
})

function submitClick(){
  var firebaseref = firebase.database().ref();
  var messageText = mainText.value;
  var txtmail = emailText.value;
  var prenomtxt = prenom.value;


  if(messageText == "" || txtmail == "" || prenomtxt == ""){
   alert("Tous les champs doivent être remplis");
   return;
  }

 firebaseref.child("user").push().set({name : messageText, prenom:prenomtxt ,email : txtmail});



 var f = firebase.database().ref().child("user").orderByChild("email").equalTo(txtmail);


 // firebaseref.child("user").push({name: messageText, prenom:prenomtxt, email: txtmail}).then(pushed_user => {
 //
 // console.log(pushed_user.key);
 //
 // });

 f.on("value", function(datasnapchot){
  var id = datasnapchot.val();
  console.log(id);

 });

// location.reload();
}

Answer 1

When you push an element you can directly retrieve the auto generated ID without having to call a listener.

firebaseref.child("user").push({name: messageText, prenom:prenomtxt, email: txtmail}).then(pushed_user => {

console.log(pushed_user.key);

});

You can find another example here .

Answer 2

尝试像函数一样调用它：

var id = datasnapchot.key();

Answer 3

var newPostKey = firebaseref.child("user").push().set({name : messageText,prenom:prenomtxt ,email : txtmail}).key;

“newPostKey”将是你的钥匙

Answer 4

Try the following:

var ref = firebase.database().ref("users");

ref.push().on("value", function(snapshot) { snapshot.forEach(function(childSnapshot) {
var id = childSnapshot.key();
console.log(childSnapshot);
  });
});

You need to loop using forEach and then you will be able to retrieve the push key using key()

Answer 5

This worked for me

var id = datasnapchot.key;

Use datasnapchot.key instead of datasnapchot.key()