Replace a value in NSDictionary in iPhone

Question

I have a array (dataArray) of NSDictionary \"item\". It has datas like \"david\" for key \"name\" and \"85\" for key \"marks\" etc for 5 students. I want to replace the mark

Answer 1

You first need an NSMutableDictionary with it you can change the key and value.

It would be like this:

NSMutableDictionary *dict = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"david", @"name", "85", @"marks", nil];

[dict setObject:@"90" forKey:@"david"];

Answer 2

 // NSDictionary *dict = ...
    NSMutableDictionary *mutableDict = [dict mutableCopy];
    [mutableDict setObject:@"myObject" forKey:@"myKey"];
    dict = [mutableDict mutableCopy];

I hope it helps

Answer 3

If you want to update an object in a NSDictionary you should use NSMutableDictionary instead. NSMutableDictionary has the following EXTRA methods

Adding Entries

• setObject:forKey:
• setValue:forKey:
• addEntriesFromDictionary:
• setDictionary:

Removing Entries

• removeObjectForKey:
• removeAllObjects
• removeObjectsForKeys:

Answer 4

Here's what you can do:

NSMutableDictionary *newDict = [[NSMutableDictionary alloc] init];
NSDictionary *oldDict = (NSDictionary *)[dataArray objectAtIndex:0];
[newDict addEntriesFromDictionary:oldDict];
[newDict setObject:@"Don" forKey:@"Name"];
[dataArray replaceObjectAtIndex:0 withObject:newDict];
[newDict release];

Hope this helps!

Answer 5

[davidsRecord setObject:@"100" forkey:@"mark"];