[flexcoders] Need to filter UTF-8 characters from string

[flex flex]

Hello All,

I have a string of which contains lots of special characters from different
standerds. I want to filter the string and want only those characters which
are supported by UTF-8.
Does anyone have any idea for this?

I have a sample string as-

!"#$%&'()*+,-./0123456789:;<=>@ABCDEFGHIJKLMNOPQRSTUVWXYZ
[\]^_`abcdefghijklmnopqrstuvwxyz{|}~"'&<>¡¢£¤¥¦§¨©ª"®¯°±²³´µ·¸¹º"¼½¾¿×÷ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýþÿŒœŠšŸƒˆ˜--''‚"""†‡o…‰‹›€™