xml Class to substitute ini files

Question

I am learning Windows Forms in C#.NET 2008 and i want to build a class to work with SIMPLE xml files (config file like INI files), but i just need a simple class (open, getvalue, setvalue, creategroup, save and close functions), to substitute of ini files.

I already did something and it is working but I am having trouble when I need to create different groups, something like this:

<?xml version="1.0" encoding="utf-8"?>
<CONFIG>
  <General>
    <Field1>192.168.0.2</Field1>
  </General>
  <Data>
    <Field1>Joseph</Field1>
    <Field2>Locked</Field2>
  </Data>
</CONFIG>

how can i specify that i want to read the field1 of [data] group? note that i have same field name in both groups (Field1)!

I am using System.Linq, something like this:

To open document:

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(FilePath);

To save document:

xmlDoc.Save(FilePath);

To get value:

public string getValue(string Field)
{
    string result = "";
    try
    {
        XmlNodeList xmlComum = xmlDoc.GetElementsByTagName(Field);
        if (xmlComum.Item(0) == null)
            result = "";
        else
            result = xmlComum.Item(0).InnerText;
    }
    catch (Exception ex)
    {
        return "";
    }
    return result;
}

To set value:

public void setValue(string Group, string Field, string FieldValue)
{
    try
    {
        XmlNodeList xmlComum = xmlDoc.GetElementsByTagName(Field);
        if (xmlComum.Item(0) == null)
        {
            xmlComum = xmlDoc.GetElementsByTagName(Group);
            if (xmlComum.Item(0) == null)
            {
                // create group
                createGroup(Group);
                xmlComum = xmlDoc.GetElementsByTagName(Group);
            }
            XmlElement xmlE = xmlDoc.CreateElement(Field);
            XmlText xmlT = xmlDoc.CreateTextNode(FieldValue);
            xmlE.AppendChild(xmlT);
            xmlComum.Item(0).AppendChild(xmlE);
        }
        else
        {
            // item already exists, just change its value
            xmlComum.Item(0).InnerText = Value;
        }
        xmlDoc.Save(FilePath);
    }
    catch (Exception ex)
    {
    }
}

The CreateGroup code:

public void createGroup(string Group)
{
    try
    {
        XmlElement xmlComum = xmlDoc.CreateElement(Group);
        xmlDoc.DocumentElement.AppendChild(xmlComum);
        xmlDoc.Save(FilePath);
    }
    catch (Exception ex)
    {
    }
}

Answer 1

Though you may be "using" System.Linq in your project, you are not using the so-called "Linq-to-XML" classes. Which make things about 5 times easier, even you're not using LINQ on them! Use the System.Linq.XML namesspace, to have access to these new xml classes (XDocument, XElement, etc.)

    XDocument XDoc = XDocument.Load("ThePath") 
    String Field1 = (String)XDoc.Root.Element("Data").Element("Field1")

• Pretty good tutorial.
• Documentation.
• Good DNR TV vid-casts here/here and here.
• A great book on Linq in general, and Linq-to-XML in particular
  

Answer 2

If you're using the XML file as an actual repository of configuration data (just like we used to use .INI files for, back in the mists of time) then System.Configuration is your friend, as it handles reading and writing to App.Config, which is an XML file designed just for this.

Here's some detail and examples: System.Configuration

Of course, if you're writing a generic interface to XML files, System.Linq.XML is the right way to go.