I have this code, but i don't know how capture a error.

  const coleccionRef = database.ref('test');
  coleccionRef.on('value', snapshot => {
    snapshot.val();
  });

Any idea?

I have this code, but i don't know how capture a error.

  const coleccionRef = database.ref('test');
  coleccionRef.on('value', snapshot => {
    snapshot.val();
  });

Any idea?

• javascript
• firebase
• firebase-realtime-database
• error-handling

Share Improve this question Follow edited Dec 5, 2017 at 15:34 Frank van Puffelen 601k8585 gold badges890890 silver badges860860 bronze badges asked Dec 5, 2017 at 11:09 allelallel 87711 gold badge1212 silver badges2222 bronze badges 1

• 1 you may check that you have a data or empty with if(snapshot.exists()) { // do something with data } else {//there is no data} firebase.google./docs/reference/js/… – Cappittall Commented Dec 5, 2017 at 11:17

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1 Answer 1

Sorted by: Reset to default 8

If your client doesn't have permission to read from the reference, Firebase will invoke the (optional) second callback that you can pass in to on(). E.g.

const coleccionRef = database.ref('test');
coleccionRef.on('value', snapshot => {
  snapshot.val();
}, error => {
    console.error(error);
});

I remend reading the Firebase reference documentation for finding more tidbits like this.