使用objectForKey从NSArray的NSDictionary获取NSarray

Question

I have a NSArray which contain n number of NSDictionary sampleArray =

 (
            {
            0 = 0;
            1 = 0;
        },
            {
            0 = 86400;
            1 = 2;
        },
            {
            0 = 172800;
            1 = 4;
        },
            {
            0 = 259200;
            1 = 5;
        }

    )

Now I need to fetch the NSArray for objectForKey 0 [sampleArray objectForKey:[NSNumber numberWithInt:0]] , my result NSArray should be like (0,86400,172800,259200) but I am unable to fetch the result and the app crashes.

Normally for NSDictionary, if key value is set using NSString valueForKey the above operation is performed successfully but if key value is set using an object like NSNumber objectForKey I am unable to perform the operation.

Please help me to get a solution, any suggestion would be appreciated!!

Answer 1

THIS doesnt work - im sorry: I didnt see you didnt have Strings as keys + I didnt know KVC only works with strings

I leave it though

---

what you are looking for is

NSArray *zeros = [mainArray valueForKey:@"0"];

it gets "0" from each dict in array

Answer 2

A very straight forward way if your keys are NSNumber objects:

NSMutableArray *result = [[NSMutableArray alloc] init];
for (NSDictionary *d in a) {
    if (d[@0]) {
        [result addObject:d[@0]];
    }
}

Answer 3

What you have do is

  NSMutableArray *arrResult = [[NSMutableArray alloc]init];
 for(int i=0;i<[sampleArray count];i++)
  {
    NSString *strValue = [[sampleArray objectAtIndex:i] valueforkey:@"0"];

   [ arrResult addobject:strValue];
 }

let me know it is working or not!!!!

Happy coding!!!!!

Answer 4

here you can try NSArray *tempArray

for (NSDictionary *list in tempArray)
{
    [firstArray addObject:[list objectForKey:@"0"];
    [secondArray addObject:[list objectForKey:@"1"];
}