How can I easily delete all objects in a Realm

问题:

I have the choice of doing a migration, but I would prefer to delete everything in my defaultRealm(). How can I do this easily?

realm.deleteObject(object)

is the only function along with .deleteObjects.

I have tried the following code:

Method 1

realm.deleteObjects(RLMObject.objectsInRealm(realm, withPredicate: NSPredicate(value: true)))

Method 2

        realm.deleteObjects(Dog.allObjectsInRealm(realm))
        realm.deleteObjects(Person.allObjectsInRealm(realm))
        realm.deleteObjects(Goal.allObjectsInRealm(realm))
        realm.deleteObjects(Goals.allObjectsInRealm(realm))

Both fail to prevent the migration exception.

回答1:

Use deleteAll():

let realm = try! Realm()
try! realm.write {
    realm.deleteAll()
}

回答2:

As of v0.87.0, there is a deleteAllObjects method on RLRealm that will clear the Realm of all objects.

回答3:

Things have moved on in the Realm world - in case anyone comes across this now, there is a property that can be set:

Realm.Configuration.defaultConfiguration.deleteRealmIfMigrationNeeded = true

It then does as advertised. (btw: a lot of the syntax above has changed in case you are trying any of the other methods)

The Github PR https://github.com/realm/realm-cocoa/pull/3463

回答4:

I think removing the Realm DB file is the valid answer considering that the question was about removing a whole storage rather than migrating it.

Here is a quick Swift code for that (as of Swift 2.1 and Realm 0.96.2):

if let path = Realm.Configuration.defaultConfiguration.path {
    try! NSFileManager().removeItemAtPath(path)
}

I use this code in the DEBUG version of the app if the migration error happens on loading the storage and then I recreate the storage. During development the schema can change a lot, so it would be too cumbersome to bother with migration all the time.