Parse.com查询数组

时间:2014-03-08 12:38:59

标签: ios objective-c parse-platform

我目前对parse.com有这个查询:

- (void)viewDidLoad
{
    PFQuery *activityQuery = [PFQuery queryWithClassName:@"Activities"];


    [activityQuery whereKey:@"triathlete" equalTo:[PFUser currentUser]];

    [activityQuery findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
        if (!error) {
            _activityArray = objects;
            NSLog(@"activityArray = %@",_activityArray);

        }
    }];

它存储了我数据库中每个对象的所有数据。我的问题是如何从单个列中获取数据,而不是从一个数组中获取所有数据。

非常感谢

2 个答案:

答案 0 :(得分:1)

如果我正确理解了您的问题,您可以在块内的不同数组中分隔列,如下所示:

[activityQuery findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
        if (!error) {
            NSMutableArray *column1 = [objects valueForKey:@"column1"];
            NSMutableArray *column2 = [objects valueForKey:@"column2"];
            NSMutableArray *column3 = [objects valueForKey:@"column3"];
        }
    }];

然后对每个Array执行任何操作。

答案 1 :(得分:0)

从查询结果中获取单个列使用以下方式

    [activityQuery findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
(if!error){   
 for(PFObject *object in objects){
        // to print individual object one by one
    NSLog(@"%@",object);
    // to retrieve individual column  if the column is string type
    NSLog(@"%@",[object objectForkey:@"yourColumnName"]);

    }
}];