<script>
var iChars = "!@#$%^&*()+=-[]\\\';,./{}|\":<>?"; 

if (/\W/.test(iChars)) { 
alert ("Your username has special characters. \nThese are not allowed.\n Please remove them and try again."); 
} 
</script>

<script>
var iChars = "b(@)u*@{lko'\-_p!c@h#$%e^&l*()k+=-[o]\\\';,./{}|\":<>?"; 

if (/\W/.test(iChars)) { 
document.write(iChars.replace(/\W/g,''));
} 
</script>
</script>