How to concatenate char and string on iPhone?

I want to add some marks to separate some strings. How to add a char to a string?

e.g. add '\x01' to "Hello", add '\x02' before "World" and add '\x03' after "World".

So I can create a string "\x01 Hello \x02 World \x03" which has some separate marks.

If you want to modify a string, you have to use NSMutableString instead of NSString. There is no such need if you want to create a string from scratch.

For instance, you may want to use +stringWithFormat: method:

NSString * myString = [NSString stringWithFormat:@"%c %@ %c %@ %c",
                                                 0x01,
                                                 @"Hello",
                                                 0x02,
                                                 @"World",
                                                 0x03];