从xml文件中提取数据

Question

I have a string XML, which I want to convert to an actual XML, and get its values.

My (string)XML document looks like that:

<Folder>
    <Files>
       <File Id="123" 
        Size="111"
        Name="abc"/>
    </Files>
</Folder> 

This is what I'm doing:

XmlDocument xml = new XmlDocument();
xml.LoadXml(stringXML);

XmlNodeList xnList = xml.SelectNodes("/Folder/Files");
foreach (XmlNode xn in xnList)
{
     string a = xn["File Id"].InnerText;
}  

Here, my xml variable (the XmlDocument) has my XML: < Folder>< Files> etc... inside the "InnerXml" property.
The xnList (XmlNodeList) has < File Id="123" Size="111" Name="abc"/> under its "InnerXml" property.
and xn the XmlNode is exactly the same as xnList, so there is no such thing as xn["File Id"] .

How can I get the information from the XML file?

Answer 1

It's not really clear what you're trying to do, but I'd suggest using LINQ to XML - it'll make things simpler:

var doc = XDocument.Parse(stringXML);
// Or doc.Root.Element("Files").Elements("File")
foreach (var file in doc.Descendants("File")) 
{
    int id = (int) file.Attribute("Id");
    int size = (int) file.Attribute("Size");
    string name = (string) file.Attribute("Name");
    // Do whatever you need...
}

Or if you just want to gather the information:

var doc = XDocument.Parse(stringXML);
var query = doc.Descendants("File").Select(file => new { 
                                Id = (int) file.Attribute("Id"),
                                Size = (int) file.Attribute("Size"),
                                Name = (string) file.Attribute("Name")
                            });

Answer 2

This is the correct way:

        var stringXML = "<Folder><Files><File Id=\"123\" Size=\"111\" Name=\"abc\"/></Files></Folder> ";
        XmlDocument xml = new XmlDocument();
        xml.LoadXml(stringXML);

        XmlNodeList xnList = xml.SelectNodes("/Folder/Files");
        foreach (XmlNode xn in xnList)
        {
            string a = xn["File"].Attributes["Id"].Value;
        }  

Answer 3

You can't straight a way fetch the attribute value for Id. You can use the attribute property to fetch that particular attribute value.

 XmlNodeList xnList = xml.SelectNodes("/Folder/Files");
    foreach (XmlNode xn in xnList)
    {
         string a = xn.Attributes["Id"].Value; // Modify likewise
    }