NSDictionary key comparison fails - ios

Question

I am dealing a very basic problem, I have two dictionary keys I need to compare but when I do it doesn't give me correct answer, somehow I am failing to create the logic.
So I have this in a plist array of dictionaries and json array comming from server
I want to compare them if event exist in plist do certain thing if not do another thing;
PROBLEM:
According to my logic if two events in plist are equal to other two events comming from server if logic should be printed per for each dictionary coming from server , so in this case 2 times total , but in my code it is printed 4 times. basically it is satisfying the condition every single time.
NSLOG:
evreka find the id
evreka find the id
evreka find the id
evreka find the id
SOURCE:
in a plist;
createList (
{
"end_date" = "2013-07-24";
ends = "13:07:00";
"event_id" = 173;
"event_name" = Static;
location = Asdad;
"root_folder" = "dadapof#gmail.com";
"start_date" = "2013-07-24";
starts = "13:07:00";
"user_id" = 13;
},
{
"end_date" = "2013-07-25";
ends = "13:08:00";
"event_id" = 174;
"event_name" = "Event Delete";
location = Asdsad;
"root_folder" = "dadapof#gmail.com";
"start_date" = "2013-07-25";
starts = "13:08:00";
"user_id" = 13;
}
)
This comming from server
responseobj (
{
"end_date" = "2013-07-24";
ends = "13:07:00";
"event_id" = 173;
"event_name" = Static;
location = Asdad;
"root_folder" = "dadapof#gmail.com";
"start_date" = "2013-07-24";
starts = "13:07:00";
"user_id" = 13;
},
{
"end_date" = "2013-07-25";
ends = "13:08:00";
"event_id" = 174;
"event_name" = "Event Delete";
location = Asdsad;
"root_folder" = "dadapof#gmail.com";
"start_date" = "2013-07-25";
starts = "13:08:00";
"user_id" = 13;
}
)
CODE:
Comparison code;
if ([[NSFileManager defaultManager] fileExistsAtPath:dataPath]){
createList= [NSMutableArray arrayWithContentsOfFile:dataPath];
NSLog(#"createList %#",createList);
NSLog(#"responseobj %#",responseObj);
//compare plist and response object
for (int i=0; i<[responseObj count]; i++) {
NSDictionary *dataDict = [responseObj objectAtIndex:i];
NSString *event_name =[dataDict objectForKey:#"event_name"];
//NSString *event_id =[dataDict objectForKey:#"event_id"];
BOOL eventExistInPlist=NO;
for (int j=0; j<[createList count]; j++) {
NSDictionary *createDict = [createList objectAtIndex:i];
//NSString *create_id =[createDict objectForKey:#"event_id"];
NSNumber *create_id =[createDict objectForKey:#"event_id"];
if ([[dataDict objectForKey:#"event_id"] isEqual:[createDict objectForKey:#"event_id"]]) {
// if (create_id==event_id) {
NSLog(#"evreka find the id");
What I have tried:
I have tried to compare them as strings(isEqualtoString), numbers(==) and isEqual: method , they have all failed.
What am I doing wrong?

Answer 1

In
NSDictionary *createDict = [createList objectAtIndex:i];
^----- HERE
you are using the wrong index, it should be j instead of i for the inner loop.

Answer 2

Martin R's answer is where your issue is. I would change your logic though to include Objective-C fast enumeration instead of the standard for ++ loop. I also separated out the second for loop into a BOOL method for easier reading
for (NSDictionary *dataDict in responseObj) {
NSString *event_name =[dataDict objectForKey:#"event_name"];
if ([self matchFoundForEventId:event_name]) {
NSLog(#"Match found");
}
}
-(BOOL)matchFoundForEventId:(NSString *)eventId {
for (NSDictionary *dataDict in createList) {
NSString *createEvent = [dataDict objectForKey:#"event_id"];
if ([eventId isEqualToString:createEvent]) {
return YES;
}
}
return NO;
}