How to check if a font supports a character?

[cspwcspw]

I run into "Font does not contain character xxx". I'd like to sanitize my strings and I'm willing to do my own character substitutions, but I cannot find a way to test if a font does support a character, or to enumerate which characters are supported. Other than to try to AddText and catch the exception.

Is there a mechanism to learn what characters are going to be safe?

Thanks