Visual Basic

Public Function GetMD5(ByVal file As String) As String
        Dim md5 As MD5CryptoServiceProvider = New MD5CryptoServiceProvider
        Dim f As FileStream = New FileStream(file, FileMode.Open, FileAccess.Read, FileShare.Read, 8192)
        md5.ComputeHash(f)
        Dim hash As Byte() = md5.Hash
        f.Close()
        Dim buff As StringBuilder = New StringBuilder
        Dim hashByte As Byte
        For Each hashByte In hash
            buff.Append(String.Format("{0:X1}", hashByte))
        Next
        Return buff.ToString()
    End Function

Public function DoChecksum(ByVal file As String) as string

        Dim csp As New MD5CryptoServiceProvider()
        Try
            Dim stm As FileStream = New FileStream(file, FileMode.Open, FileAccess.Read, FileShare.Read, 8192)
            Dim hash As Byte() = csp.ComputeHash(stm)
            stm.Close()

            Dim computed As String = BitConverter.ToString(hash).Replace("-", "")
return computed
    End function