CODEWITHSUNDEEP
iphonensarraynsdictionary
maxus182
maxus182

Reputation: 161

NSDictionary search for key and update value

I have an array of dictionaries stored in plist. Dictionary keys are: globalKey and moneyKey.

Now I'd like to search the array for a specific key value. If the key value exists, I need to update the dictionary with the new value for the other key.

Example: I need to search the key @"globalKey" for value 5. If the value 5 exists I need to update that dictionary with the new value for the key @"moneyKey" and save it to the plist.

What would be the best approach for this?

This is how I add new dictionary:

array = [NSMutableArray arrayWithContentsOfFile:filePath];
NSDictionary *newDict = [[NSDictionary alloc] init];
newDict = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:month],@"globalKey", [NSNumber numberWithFloat:money], @"moneyKey", nil];
[array addObject:newDict];
[array writeToFile:filePath atomically:YES];

Upvotes: 0

Views: 2266

Answers (2)

user843337
user843337

Reputation:

If I understand what you're trying to do correctly then I think you could try something like this:

NSMutableArray *myArray = [[NSMutableArray alloc] init]; // YOUR STARTING ARRAY OF NSDICTIONARIES

NSMutableIndexSet *indexSet = [[NSMutableIndexSet alloc] init];
NSMutableArray *dictionariesToReplace = [[NSMutableArray alloc] init];

for (int i=0; i < [myArray count]; i++) 
{
    // Pull out the value to check
    int valToCheck = [[[myArray objectAtIndex:i] valueForKey:@"globalKey"] intValue];

    // Check if a match was made
    if (valToCheck == 5) 
    {
        // Make a copy of the existing NSDictionary
        NSMutableDictionary *newDictionary = [[myArray objectAtIndex:i] mutableCopy];
        [newDictionary setValue:@"NEW VALUE" forKey:@"moneyKey"];

        // Add the dictionary to the array and update the indexset
        [dictionariesToReplace addObject:newDictionary];
        [indexSet addIndex:i];
    }
}

// Update the array with the new dictionaries
[myArray replaceObjectsAtIndexes:indexSet withObjects:dictionariesToReplace];

Hope this helps you out.

Upvotes: 1

Nuzhat Zari
Nuzhat Zari

Reputation: 3408

You can use NSPredicate to search Array of Dictionary as follows:

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"globalKey == 5"]; NSArray *predicateArray = [array filteredArrayUsingPredicate:predicate];

Upvotes: 0

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