Question

I have this simple Xml file

<Root>
    <Licence Name="My name" Age="23"/>
</Root>

During my encryption and decryption process, I’m using ToBase64String() andFromBase64String() methods, but it does not seam to work, when I try to decrypt the file, the <> witch limit my Licence element are lost. here’s the result after encryption and decryption :

<Root>&lt;Licence Name="My name" Age="23" /&gt;</Root>

Here is my code

//Encrypt
private void bnEncrypt_Click(object sender, EventArgs e)
{
        var xDoc = XElement.Load(@"C:\Opticien\Lic.xml");
        var data = xDoc.Element("Licence").ToString();

        var dataByte = Encoding.UTF8.GetBytes(data);
        var dataEncrypted = Convert.ToBase64String(dataByte);

        xDoc.SetValue(dataEncrypted);
        xDoc.Save(@"C:\Opticien\Lic.xml");
        memoEdit1.Text = xDoc.ToString();
}

//Decrypt
private void bnDecrypt_Click(object sender, EventArgs e)
{
        var xDoc = XElement.Load(@"C:\Opticien\Lic.xml");
        var data = xDoc.Value;

        var dataByte = Convert.FromBase64String(data);
        var dataDecrypted = Encoding.UTF8.GetString(dataByte);

        xDoc.SetValue(dataDecrypted);
        xDoc.Save(@"C:\Opticien\Lic.xml");
        memoEdit1.Text = xDoc.ToString();
}

Answer 1

You are using SetValue in xDoc.SetValue(dataDecrypted);. This sets the text of the <Root> node, escaping any special characters like the ‘<‘ and ‘>’ characters.

Instead, use XElement.Parse() to create a new XElement based in the decoded (rather than decrypted) string.