NSPredicate与AND和OR问题

Question

我有以下NSPredicate：

 fetchRequest.predicate = [NSPredicate predicateWithFormat:@"url = %@ AND type = %@ OR type = %@", newsStory.url, [NSNumber numberWithInt:StoryHighlighted], [NSNumber numberWithInt:StorySavedAndHighlighted]];

我想用这个特定的URL和类型（突出显示或突出显示并保存）来获取故事。但是上面的查询似乎不起作用。我做错了什么？

Answer 1

就像将OR包装在括号中以避免混淆一样简单吗？

fetchRequest.predicate = [NSPredicate predicateWithFormat:@"url = %@ AND (type = %@ OR type = %@)", newsStory.url, [NSNumber numberWithInt:StoryHighlighted], [NSNumber numberWithInt:StorySavedAndHighlighted]];

Answer 2

您可以尝试这样做：

fetchRequest.predicate = [NSPredicate predicateWithFormat:@"url = '%@' AND( type = %@ OR type = %@"), newsStory.url, [NSNumber numberWithInt:StoryHighlighted], [NSNumber numberWithInt:StorySavedAndHighlighted]];