Public Function StringEncrypt(ByVal strSource As String) As String
        Dim memStream As New MemoryStream  'Create memory stream to hold 
        ' encrypted string
        Try
            Dim bufSource() As Byte = Encoding.UTF8.GetBytes(strSource)
            Dim crStream As New CryptoStream(memStream, objDES.CreateEncryptor( _
              TheKey, Vector), CryptoStreamMode.Write)
            crStream.Write(bufSource, 0, bufSource.Length)
            crStream.FlushFinalBlock()
            Return Convert.ToBase64String(memStream.ToArray())
        Catch ex As Exception
            Throw New ApplicationException("String encryption Error.")
        End Try
    End Function
    Public Function StringDecrypt(ByVal strSource As String) As String
        Dim memStream As New MemoryStream  'Create memory stream to hold 
        ' decypted string
        Dim objDecode As System.Text.Encoding = System.Text.Encoding.UTF8 ' 
        ' Memory Decode Object
        Try
            Dim bufSource() As Byte = Convert.FromBase64String(strSource)
            Dim crStream As New CryptoStream(memStream, objDES.CreateDecryptor( _
              TheKey, Vector), CryptoStreamMode.Write)
            crStream.Write(bufSource, 0, bufSource.Length)
            crStream.FlushFinalBlock()
            Return objDecode.GetString(memStream.ToArray())
        Catch ex As Exception
            Throw New ApplicationException("String decryption Error.")
        End Try
    End Function

Private arrFiles() As String
    Private Function GetFileContents(ByVal FullPath As String) As String
        Dim strContents As String
        Dim objReader As StreamReader
        Try
            objReader = New StreamReader(FullPath)
            strContents = objReader.ReadToEnd()
            objReader.Close()
            Return strContents
        Catch Ex As Exception
            Throw New ApplicationException("Read Input File Error.")
        End Try
    End Function
    Private Function SaveTextToFile(ByVal strData As String, ByVal FullPath As _
      String) As Boolean
        Dim bAns As Boolean = False
        Dim objReader As StreamWriter
        Try
            objReader = New StreamWriter(FullPath)
            objReader.Write(strData)
            objReader.Close()
            bAns = True
        Catch Ex As Exception
            Throw New ApplicationException("Write Ouput File Error.")
        End Try
        Return bAns
    End Function

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