VB Forum / General / December 2004

This is the code I use for numeric only;

Public Function ValidateNumeric(ByVal strText As String) As Boolean

On Error GoTo Hell

' NumValue contains the string to test
If strText Like "#" Or (Len(strText) > 1 And Left$(strText, _
   1) Like "[-+.0-9]" And Not Mid$(strText, 2) Like "*[!.0-9]*" And Not _
   strText Like "*.*.*") Then ValidateNumeric = True

Exit Function

Hell:
   ValidateNumeric = False

End Function

Here are two functions that I have posted in the past for similar
questions..... one is for digits only and the other is for "regular"
numbers:

    Function IsDigitsOnly(Value As String) As Boolean
        IsDigitsOnly = Len(Value) > 0 And _
                       Not Value Like "*[!0-9]*"
    End Function

    Function IsNumber(ByVal Value As String) As Boolean
        '   Leave the next statement out if you don't
        '   want to provide for plus/minus signs
        If Value Like "[+-]*" Then Value = Mid$(Value, 2)
        IsNumber = Not Value Like "*[!0-9.]*" And _
                          Not Value Like "*.*.*" And _
                          Len(Value) > 0 And Value <> "." And _
                          Value <> vbNullString
    End Function

Here are revisions to the above functions that deal with the local
settings for decimal points (and thousand's separators) that are
different than used in the US.

    Function IsNumber(ByVal Value As String) As Boolean
      Dim DP As String
      '   Get local setting for decimal point (do not
      '   modify this statement, it is correct as written)
      DP = Format$(0, ".")
      '   Leave the next statement out if you don't
      '   want to provide for plus/minus signs
      If Value Like "[+-]*" Then Value = Mid$(Value, 2)
      IsNumber = Not Value Like "*[!0-9" & DP & "]*" And _
                 Not Value Like "*" & DP & "*" & DP & "*" And _
                 Len(Value) > 0 And Value <> DP And _
                 Value <> vbNullString
    End Function

I'm not as concerned by the rejection of entries that include one or
more thousand's separators, but we can handle this if we don't insist on
the thousand's separator being located in the correct positions (in
other words, we'll allow the user to include them for their own
purposes... we'll just tolerate their presence).

    Function IsNumber(ByVal Value As String) As Boolean
      Dim DP As String
      Dim TS As String
      '   Get local setting for decimal point (do not
      '   modify this statement, it is correct as written)
      DP = Format$(0, ".")
      '   Get local setting for thousand's separator
      '   and eliminate them. Remove the next two lines
      '   if you don't want your users being able to
      '   type in the thousands separator at all.
      TS = Mid$(Format$(1000, "#,###"), 2, 1)
      Value = Replace$(Value, TS, "")
      '   Leave the next statement out if you don't
      '   want to provide for plus/minus signs
      If Value Like "[+-]*" Then Value = Mid$(Value, 2)
      IsNumber = Not Value Like "*[!0-9" & DP & "]*" And _
                 Not Value Like "*" & DP & "*" & DP & "*" And _
                 Len(Value) > 0 And Value <> DP And _
                 Value <> vbNullString
    End Function

Rick - MVP