NSDictionary筛选和排序 [英] NSDictionary Filtering and Sorting
本文介绍了NSDictionary筛选和排序的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在开发一个使用JSON API的应用程序，并且正在使用Objective C Framework的JSON将数据放入NSDictionary中.字典看起来像这样:
I am working on a App that makes use of a JSON API and I am Using the JSON for Objective C Framework to get the Data into a NSDictionary. The dictionary loos like this:
({
admitted = "<null>";
agreed = "<null>";
"area_id" = 1;
"area_name" = "Digitales, Urheber-/Patentrecht, Datenschutz";
created = "2010-08-17 12:41:03";
"current_draft_content" = Bla Bla Bla";
"current_draft_created" = "2010-08-17 12:42:44";
"current_draft_formatting_engine" = compat;
"discussion_url" = "http://piratenpad.de/OpenSourceZwang";
id = 502;
"informed_supporter_count" = 11;
"issue_accepted" = "";
"issue_admission_time" = "8 days";
"issue_closed" = "";
"issue_created" = "2010-08-17 12:41:03";
"issue_discussion_time" = "15 days";
"issue_fully_frozen" = "";
"issue_half_frozen" = "";
"issue_id" = 242;
"issue_population" = 372;
"issue_ranks_available" = 0;
"issue_state" = new;
"issue_verification_time" = "8 days";
"issue_vote_later" = 0;
"issue_vote_now" = 0;
"issue_voter_count" = "<null>";
"issue_voting_time" = "8 days";
name = "Alte & unsupportete Software, muss Open Source werden";
"negative_votes" = "<null>";
"policy_initiative_quorum_den" = 100;
"policy_initiative_quorum_num" = 10;
"policy_issue_quorum_den" = 100;
"policy_issue_quorum_num" = 10;
"policy_majority_den" = 2;
"policy_majority_num" = 1;
"policy_majority_strict" = 1;
"positive_votes" = "<null>";
rank = "<null>";
revoked = "<null>";
"satisfied_informed_supporter_count" = 7;
"satisfied_supporter_count" = 7;
"suggested_initiative_id" = "<null>";
"supporter_count" = 11;
},
{
admitted = "<null>";
agreed = "<null>";
"area_id" = 1;
"area_name" = "Digitales, Urheber-/Patentrecht, Datenschutz";
created = "2010-08-17 14:09:14";
"current_draft_content" = "Bla Bla Bla";
"current_draft_created" = "2010-08-17 14:09:31";
"current_draft_formatting_engine" = compat;
"discussion_url" = "";
id = 508;
"informed_supporter_count" = 0;
"issue_accepted" = "2010-08-14 01:51:45";
"issue_admission_time" = "15 days";
"issue_closed" = "";
"issue_created" = "2010-08-14 01:34:26";
"issue_discussion_time" = "30 days";
"issue_fully_frozen" = "";
"issue_half_frozen" = "";
"issue_id" = 30;
"issue_population" = 603;
"issue_ranks_available" = 0;
"issue_state" = accepted;
"issue_verification_time" = "15 days";
"issue_vote_later" = 9;
"issue_vote_now" = 0;
"issue_voter_count" = "<null>";
"issue_voting_time" = "15 days";
name = "Grundrecht: Alternative Formulierung";
"negative_votes" = "<null>";
"policy_initiative_quorum_den" = 100;
"policy_initiative_quorum_num" = 10;
"policy_issue_quorum_den" = 100;
"policy_issue_quorum_num" = 10;
"policy_majority_den" = 3;
"policy_majority_num" = 2;
"policy_majority_strict" = 0;
"positive_votes" = "<null>";
rank = "<null>";
revoked = {
};
"satisfied_informed_supporter_count" = 0;
"satisfied_supporter_count" = 0;
"suggested_initiative_id" = "<null>";
"supporter_count" = 0;
}
)
什么是获取"issue_id"为2或6以上的所有对象的好方法，或者显示成组的UITabeView并将具有相同"issue_id"的所有对象归为一组的一种好方法?
What is a good way to get all object where the "issue_id" is 2 oder 6 or what ever to display a grouped UITabeView with all objects with the same "issue_id" in one group?
推荐答案
您可以使用NSSortDescriptor进行排序:
You can use NSSortDescriptor to sort:
NSSortDescriptor *dateSortDescriptor = [[[NSSortDescriptor alloc] initWithKey:@"issue_id" ascending:YES selector:@selector(compare:)] autorelease];
[youDictionaryArray sortUsingDescriptors:[NSArray arrayWithObjects:dateSortDescriptor, nil]];
和/或NSPredicate仅获得一些ID:
And/or NSPredicate to get some ID only:
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"(issue_id == %i)", 2];
NSArray *newArray = [youDictionaryArray filteredArrayUsingPredicate:predicate];
这篇关于NSDictionary筛选和排序的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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