how to iterate nested dictionaries in objective-c iphone sdk

Question

Hi I have a json string converted unsing the JSON framework into a dictionary and I need to extract its content. How could I iterate to the nested dictionaries? I have alrea

Answer 1

The header of the category:

#import 

@interface NSDictionary(Find)

-(id) findflat:(NSString*)keyToFind;

@end

The body:

#import "NSDictionary+Find.h"

@implementation NSDictionary(Find)

-(id) findflat:(NSString*)keyToFind{

    if([self objectForKey:keyToFind])
        return self[keyToFind];

    for(id key in self)
        if([[self objectForKey:key] isKindOfClass:[NSDictionary class]])
            return [[self objectForKey:key] findflat:keyToFind];


    return nil;
}

@end

Usage/Validation:

- (void)testExample {
// This is an example of a functional test case.
// Use XCTAssert and related functions to verify your tests produce the correct results.

NSDictionary *dic = @{};
XCTAssertNil([dic findflat:@"url"]);

dic = @{@"url":@"http://"};
XCTAssertEqual([dic findflat:@"url"],@"http://");

dic = @{@"other":@4};
XCTAssertNil([dic findflat:@"url"]);

dic = @{@"other":@4,@"url":@"http://"};
XCTAssertEqual([dic findflat:@"url"],@"http://");

dic = @{@"other":@4,@"sd":@"sdf"};
XCTAssertNil([dic findflat:@"url"]);

dic = @{@"other":@4,@"dic":@{@"url":@"http://"}};
XCTAssertEqual([dic findflat:@"url"],@"http://");

dic = @{@"other":@4,@"dic":@{@"sd":@2,@"url":@"http://"}};
XCTAssertEqual([dic findflat:@"url"],@"http://");

dic = @{@"other":@4,@"dic":@{}};
XCTAssertNil([dic findflat:@"url"]);

dic = @{@"other":@4,@"dic":@{@"dic":@{@"sd":@2,@"url":@"http://"}}};
XCTAssertEqual([dic findflat:@"url"],@"http://");

}