Imports System.Text
Imports System.Text.RegularExpressions

Public Class ClassHelper
    Public Shared Function encode_utf8(ByVal str As String) As String
        Try
            'supply True as the construction parameter to indicate
            'that you wanted the class to emit BOM (Byte Order Mark)
            'NOTE: this BOM value is the indicator of a UTF-8 string
            Dim utf8Encoding As New System.Text.UTF8Encoding(True)
            Dim encodedString() As Byte
            encodedString = utf8Encoding.GetBytes(str)
            If LogErrorsOnly = False Then ClassLogger.Add(String.Format(" >> String {0} was encoded via utf8 to {1}", str, utf8Encoding.GetString(encodedString)), False)
            Return utf8Encoding.GetString(encodedString)
        Catch ex As Exception
            ClassLogger.Add("Unexpected error in encode_utf8: " & ex.Message)
            Return Nothing
        End Try

    End Function
    Public Shared Function StringAsUtf8Bytes(ByVal strData As String) As Byte()
        Try
            Dim bytes() As Byte
            ' get unicode string as bytes
            bytes = Encoding.UTF8.GetBytes(strData)
            ' return byte data
            Return bytes
        Catch ex As Exception
            ClassLogger.Add("Unexpected error in StringAsUtf8Bytes: " & ex.Message)
            Return Nothing
        End Try

    End Function
    Public Shared Function CheckSpecialSigns(ByVal str As String)
        Try
            Dim pattern As String = "[!""#$%&'()*+,\-./:;<=>?@[\\\]^_`{|}~\s]"
            Dim matches As MatchCollection = Regex.Matches(str, pattern)
            Return matches.Count
        Catch ex As Exception
            ClassLogger.Add("Unexpected error in CheckSpecialSigns: " & ex.Message)
            Return 0
        End Try
    End Function

End Class