Illegal Character Comparison

Is there a faster way to go through a string to detect if there are illegal characters? This is what I am using right now.

Thank You

Code:

---

Option Explicit

Sub Main()
  'PURPOSE: Test Data
  Dim str_Data As String
  str_Data = "How are you today?"

  'PURPOSE: Illegal Characters
  Dim str_IllegalChar As String
  str_IllegalChar = "\/:*?""<>|"
 
  Dim str_Char As String
  Dim int_X As Integer
  For int_X = 1 To Len(str_Data)
    str_Char = Mid(str_Data, int_X, 1)
    If InStr(1, str_IllegalChar, str_Char) <> 0 Then
      MsgBox str_Char
    End If
  Next
End Sub

---

I take it you are interested in reporting the illegal
symbol in which case your code looks as good as anything :)

Assuming you have a TextBox for data entry, then:
If there are loads other illegal chars as well, ones that
you couldn't type but could paste into your TextBox, then
you would probably be better checking for legal characters
since most likely they will be printable.

Regards