XML Serialization produces random strings at the end? C#

Question

When seralizing a class and saving to a file, sometimes an error occurs where the serialized output looks like this:

<?xml version="1.0"?>
<Template xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <Route>Some Route</Route>
    <TradePack>Something Here</TradePack>
    <Transport />
</Template>te> ------> Notice this extra string?

The class I'm serializing looks like this:

[Serializable]
public class Template
{
    public string Route = string.Empty;
    public string TradePack = string.Empty;
    public string Transport = string.Empty;

    public Template()
    {

    }
}

I can't seem to figure out why this is happening. Here's my serializer class:

    public static bool Save(object obj, string path)
    {
        try
        {
            XmlSerializer writer = new XmlSerializer(obj.GetType());

            using (var stream = new FileStream(path, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite))
            {
                writer.Serialize(stream, obj);
            }

            return true;
        }
        catch { }
        return false;
    }

Thanks!

I had a similar problem once, on my end it was the fault that the file never got cleaned completely. It was always a piece left. Maybe delete the file before you write to it. — Christoph K, Jul 07 '16 at 11:41

Dirk Vollmar · Accepted Answer · 2016-07-07T11:49:48.287

10

The additional output is likely a leftover from a previous version of the output file (having the same name).

You can solve the problem by changing the FileMode from OpenOrCreateto Create only. That way the output file is truncated if it already exists.

An even simpler method would be to use File.Create(path):

XmlSerializer writer = new XmlSerializer(obj.GetType());
using (var stream = File.Create(path))
{
    writer.Serialize(stream, obj);
}

As an aside: It is usually preferable to just let exceptions bubble up the call stack until you can do something meaningful with them. Just silently swallowing the exception and instead returning a status flag which might never be checked hides the actual problem, might lead to further issues later on and makes a problem analysis unnecessarily difficult.

edited Jul 07 '16 at 11:49

answered Jul 07 '16 at 11:42

Dirk Vollmar

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And let's mention the `File.Create(path)` shortcut. – H H Jul 07 '16 at 11:43
I've changed FileMode to Truncate and beforehand create the file if it doesn't yet exist. – J. Doe Jul 07 '16 at 11:48
@HenkHolterman This really isn't a lot of work, besides I don't like using external libs when not necessary. – J. Doe Jul 07 '16 at 12:30
2

@J.Doe: `File.Create` isn't an external library, it's part of .NET. – Dirk Vollmar Jul 07 '16 at 12:36
1

I didn't know what you had in mind, but I've used File.Create then. – J. Doe Jul 07 '16 at 13:05

XML Serialization produces random strings at the end? C#

1 Answers1