Testing for valid characters?

need a valid-character test for fonts

[Xedium]

I am making a script to generate an image of two Asian characters chosen at random from my font. The problem is, I just realized that not all the numbers from 4E00 to 9FA0 are in there. There are random missing characters, so the imae generated will more likely than not come up with blanks.

What I need is a function that'll test a Unicode char code and see if it exists in a given font. Any ideas?

[jatar_k]

I am not sure how to do this

what about an array of accepted characters, though you would probably have to limit the size of the array.