I want to get NSMutableDictionary count in iphone. I want to know how many items are in NSMutableDictionry. I tried these code to find out the solution but, not helped me lot.
NSLog(@"Count : %d", [mutableDictionary count]);
It is always returns '0'. How to get the count of NSMutableDictionary in iPhone? Thanks in advance.
Use -mutableCopy . NSDictionary *d; NSMutableDictionary *m = [d mutableCopy]; Note that -mutableCopy returns id ( Any in Swift) so you will want to assign / cast to the right type. It creates a shallow copy of the original dictionary.
[myDictionary setObject:nextValue forKey:myWord]; You can simply say: myDictionary[myWord] = nextValue; Similarly, to get a value, you can use myDictionary[key] to get the value (or nil).
An object representing a dynamic collection of key-value pairs, for use instead of a Dictionary variable in cases that require reference semantics.
In general, the collection classes (for example, NSMutableArray , NSMutableDictionary ) are not thread-safe when mutations are concerned. That is, if one or more threads are changing the same array, problems can occur.
You can find out how many key-object (key-value) pairs there are like so:
NSArray * allKeys = [mutableDictionary allKeys];
NSLog(@"Count : %d", [allKeys count]);
EDIT
Upon looking through the dictionary documentation, NSDictionary
's count
method (or property) should work as well. I think you may have been receiving 0 count because the dictionary was empty or nil. I offered my solution because I tend to care more about enumerating the keys than counting the entries directly.
Please consider the fact that you fixed the issue somewhere else.
• By actually populating the dictionary
or
• By fixing a bug where mutableDictionary was somehow nil
I run this test code and get the commented output
NSMutableDictionary * countDict = [NSMutableDictionary dictionaryWithObject:@"test" forKey:@"test"];
[countDict setObject:@"foo" forKey:@"bar"];
NSLog(@"test count %d", countDict.count); //test count 2
countDict = nil;
NSLog(@"test count %d", countDict.count); //test count 0
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With