AVOS Cloud 学习笔记（二） 功能总结（What it can do？）

标签：style   class   blog   code   tar   ext   

AVOS Cloud 学习笔记（一）   功能总结（What it can do？）

第一章、对象存储

1. 对象新建、保存、更新、删除和检索

   1 //创建新对象，根据类名
   2 AVObject *gameScore = [AVObject objectWithClassName:@"GameScore"];
   3 [gameScore setObject:[NSNumber numberWithInt:1337] forKey:@"score"];
   4 [gameScore setObject:@"Steve" forKey:@"playerName"];
   5 [gameScore setObject:[NSNumber numberWithBool:NO] forKey:@"cheatMode"];
   6 [gameScore save];

   1 //保存对象到服务器
   2 [gameScore save];
   3 //后台保存
   4 [gameScore saveInBackground];
   5 [gameScore saveInBackgroundWithBlock:^(BOOL successed, NSError* error){/*do somthing*/}];e

   1 //更新
   2 [gameScore refresh]

   1 //删除对象
   2 [gameScore deleteInBackground];
   3 [gameScore deleteInBackgroundWithBlock:...];
   4 [gameScire delete]//不推荐

   1 //如果有objectId的话
   2 AVQuery *query = [AVQuery queryWithClassName:@"GameScore"];
   3 AVObject *gameScore = [query getObjectWithId:@"51a90302e4b0d034f61623b5"];
   4 //访问对象的属性
   5 int score = [[game Score objectForKey:"score"]intValue];

    

2. 计数器和数组

   1 //计数器
   2 [gameScore incrementKey:@"score"];
   3 [gameScore saveInBackground];
   4 //数组 添加元素到数组末尾
   5 [gameScore addOject:"100" forKey:"some"];
   6 //添加元素到对应位置，如果字段不存在，就创建
   7 [gameSocre addUniqueObject:""forKey"ss"];
   8 //移除
   9 [gameScore removeObject: forKey:];

3. 对象离线存储和离线情况下从缓存加载

    1 // Create the object.
    2 AVObject *gameScore = [AVObject objectWithClassName:@"GameScore"];
    3 [gameScore setObject:[NSNumber numberWithInt:1337] forKey:@"score"];
    4 [gameScore setObject:@"Sean Plott" forKey:@"playerName"];
    5 [gameScore setObject:[NSNumber numberWithBool:NO] forKey:@"cheatMode"];
    6 [gameScore setObject:[NSArray arrayWithObjects:@"pwnage", @"flying", nil] forKey:@"skills"];
    7 [gameScore saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
    8 
    9     [gameScore setObject:[NSNumber numberWithBool:YES] forKey:@"cheatMode"];
   10     [gameScore setObject:[NSNumber numberWithInt:1338] forKey:@"score"];
   11     [gameScore saveEventually];
   12 }];

   AVQuery *query = [AVQuery queryWithClassName:@"GameScore"];
   query.cachePolicy = kPFCachePolicyNetworkElseCache;
   /*
   kPFCachePolicyIgnoreCache 查询行为不从缓存中加载，也不会将结果保存到缓存中。
   kPFCachePolicyIgnoreCache 是默认的缓存策略。
   kPFCachePolicyCacheOnly    查询行为会忽略网络状况，只从缓存中加载。如果没有缓存的结果，这个策略会导致一个 AVError
   kPFCachePolicyCacheElseNetwork -- 查询行为首先尝试从缓存中加载，如果加载失败, 它会通过网络加载结果。如果缓存和网络中获取的行为都失败了，会有一个 AVError
   kPFCachePolicyNetworkElseCache -- 查询行为首先尝试从网络中加载，如果加载失败, 它会从缓存中加载结果。如果缓存和网络中获取的行为都失败了，会有一个 AVError
   kPFCachePolicyCacheThenNetwork -- 查询首先从缓存中加载，然后从网络加载。在这种情况下, 回调函数会被调用两次，第一次是缓存中的结果，然后是从网络获取的结果。因为它在不同的时间返回两个结果，这个缓存策略不能和 findObjects 同时使用。
   */
   //设置缓存有效期
   query.maxCacheAge = 24*3600;
   
   [query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
     if (!error) {
       // Results were successfully found, looking first on the
       // network and then on disk.
     } else {
       // The network was inaccessible and we have no cached data for
       // this query.
     }
   }];
   
   
   // Then, elsewhere in your code...
   AVQuery *query = [AVQuery queryWithClassName:@"GameScore"];
   query.cachePolicy = kPFCachePolicyNetworkElseCache;
   [query findObjectsInBackgroundWithTarget:self
                                   selector:@selector(findCallback:error:)];

    

4. 关系型数据

    1 //1对1 对象关联
    2 // Create the post
    3 AVObject *myPost = [AVObject objectWithClassName:@"Post"];
    4 [myPost setObject:@"I‘m Smith" forKey:@"title"];
    5 [myPost setObject:@"Where should we go for lunch?" forKey:@"content"];
    6 
    7 // Create the comment
    8 AVObject *myComment = [AVObject objectWithClassName:@"Comment"];
    9 [myComment setObject:@"Let‘s do Sushirrito." forKey:@"content"];
   10 
   11 // Add a one-one relation between the Post and Comment
   12 [myComment setObject:myPost forKey:@"parent"];
   13 
   14 // This will save both myPost and myComment
   15 [myComment saveInBackground];
   16 
   17 //也可以不要对象，用objectId关联
   18 // Add a relation between the Post with objectId "51a902d3e4b0d034f6162367" and the comment
   19 [myComment setObject:[AVObject objectWithoutDataWithClassName:@"Post" objectId:@"51a902d3e4b0d034f6162367"]
   20               forKey:@"parent"];
   21 
   22 //n对n
   23 AVUser *user = [AVUser currentUser];
   24 AVRelation *relation = [user relationforKey:@"likes"];
   25 [relation addObject:post];
   26 [user saveInBackground];
   27 [relation removeObject:post];

    

第二章、数据查询

第三章、ACL权限控制

第四章、文件

第五章、用户

第六章、地理位置

第七章、调用云代码

第八章、消息推送

第九章、SNS组件

第十章、事件流

第十一章、反馈

第十二章、应用内搜索

第十三章、应用间数据绑定

AVOS Cloud 学习笔记（二） 功能总结（What it can do？）,布布扣,bubuko.com

AVOS Cloud 学习笔记（二） 功能总结（What it can do？）

标签：style   class   blog   code   tar   ext   

原文地址：http://www.cnblogs.com/lizhengfeng/p/3799121.html