Help!something about font and unicode in symbian!

    I'm writing Chinese application. So I use the Chinese font file in system. As we konw, each Chinese character maps to a unicode in the font file. Now I want to check from 0000-ffff, which unicode has been used in the font file. In other words, is there any API providing such server: I input a unicode and it will return a TBoo valuel. True means the unicode has been used in the font file. Otherwise returns Efalse.