从Dictionary中检查布尔值.

Question

我有一个变量叫做参加从JSON提要中提取.在检查对象被解释为什么类类型之后我将其作为NSLog:

attending var type is: __NSCFBoolean

这是使用[varname class]来获取变量的类类型.

所以我想看看这是真还是假....所以我写这段代码..:

if([[_events objectAtIndex:indexPath.row] objectForKey:@"attending"] == YES){

但是我无法编译它因为它给我一个黄色文本错误说:

我究竟做错了什么？我怎样才能解决这个问题.只是在Feed中添加数据如下所示:

    {
    attendees =         (
    );
    attending = 1;
    date = "2012-09-24 09:11:00";
    id = 504;
    lessonHTML = "somehtml.";
    name = "Sup";
    youtubeId = "http://www.youtube.com/watch?v=j1vb4cND3G0";
},
    {
    attendees =         (
    );
    attending = 1;
    date = "2012-09-24 09:11:00";
    id = 503;
    lessonHTML = "somehtml.";
    name = "Sup";
    youtubeId = "http://www.youtube.com/watch?v=j1vb4cND3G0";
},
    {
    attendees =         (
    );
    attending = 0;
    date = "2012-09-24 09:11:00";
    id = 508;
    lessonHTML = "somehtml.";
    name = "Sup";
    youtubeId = "http://www.youtube.com/watch?v=j1vb4cND3G0";
},
    {
    attendees =         (
    );
    attending = 1;
    date = "2012-09-24 09:11:00";
    id = 509;
    lessonHTML = "somehtml.";
    name = "Sup";
    youtubeId = "http://www.youtube.com/watch?v=j1vb4cND3G0";
},
    {
    attendees =         (
    );
    attending = 0;
    date = "2012-09-24 09:11:00";
    id = 505;
    lessonHTML = "somehtml.";
    name = "Sup";
    youtubeId = "http://www.youtube.com/watch?v=j1vb4cND3G0";
},
    {
    attendees =         (
    );
    attending = 1;
    date = "2012-09-24 09:11:00";
    id = 506;
    lessonHTML = "somehtml.";
    name = "Sup";
    youtubeId = "http://www.youtube.com/watch?v=j1vb4cND3G0";
},

Answer 1

字典和其他容器类中的布尔值封装在NSNumber对象中(NSNumber有关详细信息,请参阅文档)

要提取值,您需要将boolValue消息发送到从字典中检索的对象,并将其与YES/NO进行比较:

NSNumber* attendingObject = [[events objectAtIndex:indexPath.row] objectForKey:@"attending"];
if ([attendingObject boolValue] == YES)
{
    ...
}

阅读有关值及其封装方式的更多信息,请参阅Apple文档中的集合类