加密与 解密！
Imports System.Security
Imports System.Security.Cryptography
Dim value As String
Dim mm As Byte() = ConvertStringToByteArray(pwd.Text)
Dim HashVal As Byte() = New MD5CryptoServiceProvider().ComputeHash(mm)
value = BitConverter.ToString(HashVal)
textbox1.text=value
这是一段加密的代码，可以用？但谁知道怎么解密！
