删除Realm对象中的属性

Question

我试图删除我的一个Realm对象中的属性，但是我不确定如何为此写入迁移。

我只是删除从我的对象的头文件的属性，但因为我得到这个错误，没有工作：

Terminating app due to uncaught exception 'RLMException', reason: 'Migration is required for object type 'Stock' due to the following errors: - Property 'percentageOn' is missing from latest object model.'

我知道怎么写迁移添加字段，但我怎么去除呢？

Answer 1

大卫说的是正确的。如果您确保正确执行迁移，则Realm可以轻松处理已删除和添加的属性。除非你居然还需要percentageOn的价值，你甚至可以离开迁移块空就像在领域网站的例子：

// Inside your [AppDelegate didFinishLaunchingWithOptions:] 

// Notice setSchemaVersion is set to 1, this is always set manually. It must be 
// higher than the previous version (oldSchemaVersion) or an RLMException is thrown 
[RLMRealm setSchemaVersion:1 
      forRealmAtPath:[RLMRealm defaultRealmPath] 
     withMigrationBlock:^(RLMMigration *migration, NSUInteger oldSchemaVersion) { 
    // We haven’t migrated anything yet, so oldSchemaVersion == 0 
    if (oldSchemaVersion < 1) { 
    // Nothing to do! 
    // Realm will automatically detect new properties and removed properties 
    // And will update the schema on disk automatically 
    } 
}]; 

// now that we have called `setSchemaVersion:withMigrationBlock:`, opening an outdated 
// Realm will automatically perform the migration and opening the Realm will succeed 
[RLMRealm defaultRealm];