Copy a $firebaseObject and save it to a different location

问题

In my application i'm getting an object from my firebase using $firebaseObject. The use has two options with this object, change it and save the changes in the object or change it and save it as a new version.

My problem is getting the second option to work. For the first i can simply use $save() and it works perfectly but so far i haven't been able to make a copy of the object and save it in a different location in my firebase.

So far i have tried:

Saving the actual object in a different location (Error: Firebase.push failed: first argument contains an invalid key ($$conf) in property)
Usin angular.copy($firebaseObject) to make a copy of the object (Error: 'length' getter called on an object that does not implement interface Storage.)
Using $value of the $firebaseObject (Gives undefined because my object isn't a primitive, see $value documentation)
Making a seperate object in javascript and manually copy all the values from the $firebaseObject

The first 3 options failed (error codes are shown with the options) and the last option works but is not really an option because the object can have different fields.

Does anyone know a solution for this problem?

回答1:

You can use $value field of $firebaseObject.

for instance:

var ref = new Firebase("https://<YOUR-FIREBASE-APP>.firebaseio.com");
var FBObj1 = $firebaseObject(ref.child('child'));
ref.child('newChild').set(FBObj1.$value);

EDIT:

Since this only works for primitives, you can try something like this:

function getObject(obj) {
    var newObj = {};
    for (var key in obj) {
       if (key.indexOf('$') < 0 && obj.hasOwnProperty(key)) {
          newObj[key] = obj[key];
       };
    }
    return newObj;
}

and use getObject(FBObj1) insetad of FBObj1.$value

回答2:

Incredibly useful answer. Adding my own solution which is just an expansion on Frane and using Angularfire 2.3:

End result:

Bind first object to DOM When saving first object, save same object to another node using the same key to allow for future cross-reference In theory, you can also insert fields if needed before saving to node #2

The html:

<a href="#" editable-text="data.field1" onaftersave="saveData()">
{{ data.field1 || "empty"  }}
</a>

<a href="#" editable-text="data.field2" onaftersave="saveData()">
{{ data.field2 || "empty"  }}
</a>

In the controller:

var ref = firebase.database().ref().child(entries);
var obj = $firebaseObject(ref);
obj.$bindTo($scope, "data");


function saveData(){
    $scope.data.$save().then(function() {
        var newObject = getObject($scope.data);
        // In theory, add other field here
        var ref2 = firebase.database().ref().child(otherNode).child($scope.data.$id);
        ref2.update(newObject);
    }).catch(function(error) {
        console.log('Error ' + error.message);
    });
}

function getObject(obj) {
    var newObj = {};
    for (var key in obj) {
        if (key.indexOf('$') < 0 && obj.hasOwnProperty(key)) {
            newObj[key] = obj[key];
        };
    }
    return newObj;
}

来源：https://stackoverflow.com/questions/35508291/copy-a-firebaseobject-and-save-it-to-a-different-location

标签

angularjs

firebase

angularfire