create xml file from xml stored in a DB

[maylortaylor]

I have a table in my database that has a 3 fields.

RuleID | RuleName | Rule

the ruleID is a randomly generated string of characters, RuleName is the name the user gives to the rule, and the Rule field is about 600 characters long and is just XML text.

I want to read that Rule field from the database and use it inside the function below.

private static List<MenuItem> LoadRules(bool evaluationType)
        {
            //string path = HttpContext.Current.Server.MapPath(string.Format("/Rules/{0}/{1}/", ip, evaluationType ? "Evaluation" : "Execution"));
            List<MenuItem> list = new List<MenuItem>();
            //if(Directory.Exists(path))
            {
                //foreach(string file in Directory.GetFiles(path))
                {
                    XmlDocument xml = new XmlDocument();
 
                    xml.Load(file);
                    XmlNamespaceManager m = new XmlNamespaceManager(xml.NameTable);
                    m.AddNamespace("x", xml.DocumentElement.NamespaceURI);
                    XmlNode rule = xml.SelectSingleNode("/x:codeeffects/x:rule", m);
                    list.Add(new MenuItem(
                        rule.Attributes["id"].Value,
                        rule.SelectSingleNode("x:name", m).InnerText,
                        rule.SelectSingleNode("x:description", m) == null ? null : rule.SelectSingleNode("x:description", m).InnerText));
                }
            }
            return list;
        }

This function loads an xml file from a static location and parses out some information to a context menu.

BUt i'm culeless on how to have the function read the xml info found inside my database.

I'm a rookie at C# so be gentle

[maylortaylor]

Ok, i got part of it figured out but now i'm getting some "object refernce" error.

private static List<MenuItem> LoadRules(bool evaluationType)
        {
            string path = HttpContext.Current.Server.MapPath(string.Format("/Rules/{0}/{1}/", ip, evaluationType ? "Evaluation" : "Execution"));
            string xmlstring = LoadRuleXmlFromDB();
            File.WriteAllText(path + "rule.xml", xmlstring);
 
            List<MenuItem> list = new List<MenuItem>();
            //if(Directory.Exists(path))
            {
                foreach(string file in Directory.GetFiles(path))
                {
 
                    XmlDocument xml = new XmlDocument();
                    xml.Load(file);
                    XmlNamespaceManager m = new XmlNamespaceManager(xml.NameTable);
                    m.AddNamespace("x", xml.DocumentElement.NamespaceURI);
                    XmlNode rule = xml.SelectSingleNode("/x:codeeffects/x:rule", m);
                    list.Add(new MenuItem(
                        rule.Attributes["id"].Value,
                        rule.SelectSingleNode("x:name", m).InnerText,
                        rule.SelectSingleNode("x:description", m) == null ? null : rule.SelectSingleNode("x:description", m).InnerText));
                }
            }
            return list;
        }

As you can see, i created a string xmlstring, loaded my xml from the DB into the string, then wrote the string to a 'rule.xml' file.

But now, i'm getting "object reference not set to an instance of an object" once the code gets to the

list.Add(new MenuItem(
                        rule.Attributes["id"].Value,
                        rule.SelectSingleNode("x:name", m).InnerText,
                        rule.SelectSingleNode("x:description", m) == null ? null : rule.SelectSingleNode("x:description", m).InnerText));

part.

Upon further probing, i have found that the "rule" is null. Not sure why this is happening.