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copied!<p>I used to run into all sorts of bugs making an Xml Singleton class and ended up scrapping it as I had handles all over the place. I replaced it with using two ways. One a read-only version that was for reading data, and a second Using method/statement for writing changes. </p> <p>This in general is the pattern I use:</p> <pre><code>public class Settings : IDisposable { string file = "my settings file"; XElement root; private Settings() { root = XElement.Load(file); } private void Dispose() { root.Save(file); } public static Settings Read { get { return new Settings(); } } // return read-only version public static void Write(Action<Settings> handler) { using(Setting settings = new Settings()) handler(settings); } // below here is implentation specific public XElement Root { get { return root; } } public string SettingA { get { return (string)(Root.Attribute("SettingA") ?? (object)string.Empty); } set { Set(Root, "SettingsA", value, true); } } // I wrote this for another StackOverflow thread /// <summary> /// Set any value via its .ToString() method. /// <para>Returns XElement of source or the new XElement if is an ELEMENT</para> /// </summary> /// <param name="isAttribute">true for ATTRIBUTE or false for ELEMENT</param> /// <returns>source or XElement value</returns> private XElement Set(XElement source, string name, object value, bool isAttribute) { string sValue = value.ToString(); XElement eValue = source.Element(name), result = source; XAttribute aValue = source.Attribute(name); if (null != eValue) eValue.ReplaceWith(result = new XElement(name, sValue)); else if (null != aValue) aValue.ReplaceWith(new XAttribute(name, sValue)); else if (isAttribute) source.Add(new XAttribute(name, sValue)); else source.Add(result = new XElement(name, sValue)); return result; } /// <summary> /// Replace with for XAttribute /// </summary> /// <param name="source"></param> /// <param name="value"></param> /// <returns></returns> public static XAttribute ReplaceWith(this XAttribute source, XAttribute value) { XElement parent = source.Parent; if (null == parent) throw new Exception("Source has no parent"); source.Remove(); parent.Add(value); return value; } } </code></pre> <p>I've not used the serializer, so don't know if my pattern will fit for you. I prefer XElement.</p> <p>So to use this you'd probably write a singleton class that makes use of your non-singleton XmlSerialize class. You'd only access it through the singleton.</p> <p>But this is how I'd end up using it as is:</p> <pre><code>string settingA = Settings.Read.SettingA; </code></pre> <p>To save a value it would be:</p> <pre><code>Settings.Write(s => s.SettingA = "new value"); </code></pre>

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