An option:
[NSString stringWithFormat:@"%@/%@/%@", one, two, three];
Another option:
I'm guessing you're not happy with multiple appends (a+b+c+d), in which case you could do:
NSLog(@"%@", [Util append:one, @" ", two, nil]); // "one two"
NSLog(@"%@", [Util append:three, @"/", two, @"/", one, nil]); // three/two/one
using something like
+ (NSString *) append:(id) first, ...
{
NSString * result = @"";
id eachArg;
va_list alist;
if(first)
{
result = [result stringByAppendingString:first];
va_start(alist, first);
while (eachArg = va_arg(alist, id))
result = [result stringByAppendingString:eachArg];
va_end(alist);
}
return result;
}
You should create a header file like
// Constants.h
FOUNDATION_EXPORT NSString *const MyFirstConstant;
FOUNDATION_EXPORT NSString *const MySecondConstant;
//etc.
(you can use extern
instead of FOUNDATION_EXPORT
if your code will not be used in mixed C/C++ environments or on other platforms)
You can include this file in each file that uses the constants or in the pre-compiled header for the project.
You define these constants in a .m file like
// Constants.m
NSString *const MyFirstConstant = @"FirstConstant";
NSString *const MySecondConstant = @"SecondConstant";
Constants.m should be added to your application/framework's target so that it is linked in to the final product.
The advantage of using string constants instead of #define
'd constants is that you can test for equality using pointer comparison (stringInstance == MyFirstConstant
) which is much faster than string comparison ([stringInstance isEqualToString:MyFirstConstant]
) (and easier to read, IMO).
Best Answer
Either via:
or via:
Being a subclass of NSString however you can just cast it to an NSString
making it appear immutable, even though it in fact stays mutable.
Many methods actually return mutable instances despite being declared to return immutable ones.