How to change NSString value while debugging in Xcode?

Question

When I\'m stopped at a break point in Xcode, I can see the value of NSString variables. How can I change them? I can change int or double variables, but not NSString.

Answer 1

You can but you have to call code from the debugger command prompt. For example, say you have a breakpoint fire off right after this line:

NSString *myString = @"My current string";

Then at the (gdb) prompt type:

call myString = @"My new string"

You can po myString before changing the string and after you change it to verify that it has changed.

Another example: Say you wanted to change a view controller's title. You can use the setter. *Note: dot notation is not supported at the debugger command line. For example let the view load and then set a breakpoint somewhere during the lifetime of your view controller. Then do this:

call (id)[self setTitle:@"New Title"]

Continue running the program and you should see your view controller's title update.