Loop through NSArray of objects that has no id's - Objective C - ios

Question

I have an NSArray that looks like the following
[{
"Id":"456",
"Type":"Dog",
"Sound":"Bark",
},
{
"Id":"789",
"Type":"Cat",
"Sound":"Meow",
}]
I tried the following
for (id key in array) { // Doesn't work
NSLog(#"%#", key[#"Type"]);
}
and I tried
NSLog(#"%#", [array firstObject]); // Doesn't work
This doesn't work however because there is no id to access. I get an NSInvalidArgumentException for both. How would I successfully loop through the two objects that I have and print out the type?

Answer 1

It is a bit confusing, because you say:
I have an NSArray that looks like the following
[{
"Id":"456",
"Type":"Dog",
"Sound":"Bark",
},
{
"Id":"789",
"Type":"Cat",
"Sound":"Meow",
}]
but then, you also say:
NSLog(#"%#", [array firstObject]); // Doesn't work
Of course, you don't indicate what "Doesn't work" means... Does it throw an error? Does it output nothing? Does it output something, but not what you expect?
However, if you did have an array that "looks like that", then let's see what it actually is...
We can think of a Dictionary as:
{ key1:value1, key2:value2, key3:value3, etc... }
and we can think of an Array as:
[object1, object2, object3, etc...]
So, assuming your example data is structured like that in a valid NSArray, that means you have an Array of 2 Dictionary objects. If you want to output them to the console, you can do:
// log the first object in the array
NSLog(#"%#", [array firstObject]);
and the output should be a Dictionary:
{
Id = 456;
Sound = Bark;
Type = Dog;
}
You can also do:
// for each element (each Dictionary) in array, output the dictionary
for (NSDictionary *d in array) {
NSLog(#"%#", d);
}
resulting in:
...[1234:4321] {
Id = 456;
Sound = Bark;
Type = Dog;
}
...[1234:4321] {
Id = 789;
Sound = Meow;
Type = Cat;
}
and, finally:
// for each element (each Dictionary) in array
for (NSDictionary *d in array) {
// for each Key in each Dictionary
for (NSString *key in [d allKeys]) {
NSLog(#"%# - %#", key, d[key]);
}
}
which will give you:
...[1234:4321] Sound - Bark
...[1234:4321] Id - 456
...[1234:4321] Type - Dog
...[1234:4321] Sound - Meow
...[1234:4321] Id - 789
...[1234:4321] Type - Cat
Note that dictionaries are *un-ordered, so don't count on stepping through the keys in the same order each time.
Hope that makes sense. Of course, you still need to find out why you think you have a NSArray when you don't.