How to Check Alphanumeric's from webtable

[supputuri]

Please check the below code

Code:

myvalue = "Karachi (KHI1-)"

Set regexp = New RegExp
regexp.Pattern =  "[^\w\(\)\s]"
regexp.Global = True
regexp.IgnoreCase = True
set Matches = regexp.Execute(myvalue)
msgbox Matches.Count
If Matches.Count = 0 Then
    msgbox "input contains only alphanumerics and spl chars ()"
else
    For Each Match in Matches
        msgbox Match
    Next
End If