Question

I have a method in Objective-c that takes in an NSDictionary and returns the values as a space-separated NSString. This application is cross-platform, and as such I cannot use fast enumeration. This is what I have so far, followed by the output (which shows that the String is never created):

-(NSString *)stringValuesFromDict:(NSDictionary *map)
{
    NSArray *values = [map allValues];
    NSString *params = [NSString string];
    NSLog(@"values length: %d", [values count]);
    NSLog(@"values = %@", [values description]);
    for (int i = 0; i < [values count]; i++)
    {
        [params stringByAppendingString:[values objectAtIndex:i]];
        [params stringByAppendingString:@" "];
    }
    NSLog(@"params = %@", params);
    return params;
}

The NSDictionary:

{"arg1"="monkey"}

The output:

values length: 1
values = (
    monkey
)
params = 

What am I doing wrong? How can I get params to be set to monkey?

Answer 1

You need a mutable string. Change this:

NSString *params = [NSString string];

to this:

NSMutableString *params = [NSMutableString string];

Then change these:

[params stringByAppendingString:[values objectAtIndex:i]];
[params stringByAppendingString:@" "];

to these:

[params appendString:[values objectAtIndex:i]];
[params appendString:@" "];