Home/ Questions/Q 8152849
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-06T15:49:57+00:00

I am trying to insert a unicode hyphen-minus character into a text string. I

  • 0

I am trying to insert a unicode hyphen-minus character into a text string. I am seeing an “Invalid universal character” error with the following:

u+002D (hyphen-minus)

[textViewContent insertString:@"\u002D" atIndex:cursorPosition.location];

However, these work fine:

u+2212 (minus)

[textViewContent insertString:@"\u2212" atIndex:cursorPosition.location];

u+2010 (hyphen)

[textViewContent insertString:@"\u2010" atIndex:cursorPosition.location];

I’ve poked at several of the existing Unicode discussions here, but I have not found one that explains what is different amongst my examples that causes the first one to error. Insight greatly appreciated.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Unversal character names have some restrictions on their use. In C99 and C++98 you were not allowed to use one that referred to a character in the basic character set (which includes U+002D).

    C++11 has updated this requirement so if you are inside a string or character literal then you are allowed to use a UCN that refers to basic characters. Depending on the compiler version you’re using I would guess that you could use Objective-C++11 to make your code legal.

    That said, since this character is part of ASCII and the basic character set, why don’t you just write it literally?

    @"-"
    • 0