How do I validate strings to stop XmlDocument.ToString crashing app

General
1

If a user loads data into my app selecting an incorrect text encoding and then saves this data to an XML file my app can crash. Here is code to illustrate a crash:

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Dim s As String = “aáæ”
Dim s2 As String = ConvertEncoding(s, Encodings.MacRoman)

Dim doc as new XmlDocument
'Dim root as XmlNode = doc.CreateElement(s) // Works
Dim root as XmlNode = doc.CreateElement(s2) // Causes crash
doc.AppendChild root

Dim data as String = doc.ToString

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On macOS 10.15.7 I get a “AppName quit unexpectedly.” error when ‘doc.ToString’ is called. I see other XmlDocument.ToString issues in Feedback that haven’t been addressed so wondering if there’s a good way to validate the strings that are placed in the XML document to avoid this crash.

Thanks Mark

Xojo 2021r1.1

2

You need to convert your text to utf8. If you think your users really screw up then use CheckUTF8MBS from the MBS plugin.

3

Thanks Beatrix