Check If Child Exists Firebase Database Android Code Example


Example: firebase check if child exists

// Assume we have the following data in the Database: {   "name": {     "first": "Ada",     "last": "Lovelace"   } }  // Test for the existence of certain keys within a DataSnapshot var ref = firebase.database().ref("users/ada"); ref.once("value")   .then(function(snapshot) {     var a = snapshot.exists();  // true     var b = snapshot.child("name").exists(); // true     var c = snapshot.child("name/first").exists(); // true     var d = snapshot.child("name/middle").exists(); // false   });

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