C＃从XML文件读取

Question

I am developing an application that reads from XML files. But I am having a probling. My XML file looks like this:

<variable>
  <varName>Love</varName>
  <type>int</type>
  <value>0</value>
</variable>

And I am reading it like this:

XmlDataDocument xmldoc = new XmlDataDocument();
XmlNodeList xmlnode;
FileStream fs = new FileStream(fName, FileMode.Open, FileAccess.Read);
xmldoc.Load(fs);
xmlnode = xmldoc.GetElementsByTagName("variable");
for (int i = 0; i <= xmlnode.Count - 1; i++)
{
    Variable elem = new Variable();

    for (int j = 0; j < xmlnode[i].ChildNodes.Count; j++)
    {
        if (xmlnode[i].ChildNodes.Item(j).Name == "varName")
            elem.varName = xmlnode[i].ChildNodes.Item(j).InnerText;

        if (xmlnode[i].ChildNodes.Item(j).Name == "type")
        {
            if (xmlnode[i].ChildNodes.Item(j).InnerText == "int")
                elem.type = VariableType.INT;

            if (xmlnode[i].ChildNodes.Item(j).InnerText == "bool")
                elem.type = VariableType.BOOL;
        }

        if (xmlnode[i].ChildNodes.Item(j).Name == "value")
            elem.value = xmlnode[i].ChildNodes.Item(j).InnerText;
    }
}

After this code I should have got my elem.name="Love" elem.value=0 elem.type=INT But instead I have four elem variables first having values I want others with type="INT" others (name, value) =null. Any IDEAS. Thanks in advance.

Answer 1

at first you need an object like this:

[XmlRoot(ElementName = "variable")]
public class Variable
{
    [XmlElement(ElementName = "varName")]
    public string VarName { get; set; }

    [XmlElement(ElementName = "type")]
    public string Type { get; set; }

    [XmlElement(ElementName = "value")]
    public string Value { get; set; }

}

then deserilize your XML like this:

var result = XmlDeserializer<Variable>(File.ReadAllText("your path"));

note: here is my custom XML deserilzer:

public static T XmlDeserializer<T>(string xmlString)
{
    var instance = default(T);
    var xmlSerializer = new XmlSerializer(typeof(T));
    using (var stringreader = new StringReader(xmlString))
        instance = (T)xmlSerializer.Deserialize(stringreader);

    return instance;
}

Answer 2

Honestly it would be worth your while learning LINQ to XML. It's much easier and wouldn't take long to refactor your 1000 lines.

var map = new Dictionary<string, VariableType>()
{
    { "int", VariableType.INT },
    { "bool", VariableType.BOOL },
};

var variables =
    XDocument
        .Load("fname")
        .Root
        .Elements("variable")
        .Select(x => new Variable()
        {
            varName = x.Element("varName").Value,
            type = map[x.Element("type").Value.ToLower()],
            value = x.Element("value").Value,
        })
        .ToList();

That's it.