How to Prepare Document programatically ?

XmlDocument/XmlDataDocument objects contains CreateElement and CreateAttribute methods that are used to add nodes to the XmlDocument object.

XmlElement Contains a property Attributes Property which is an XmlAttributeCollection . this is inhirets from XmlNamedNodeMap class

Demo:

Prepare xml document programmatic:

           XmlDocument xmldoc = new XmlDocument();

           xmldoc.AppendChild(xmldoc.CreateXmlDeclaration("1.0", "utf-8", "yes"));

           XmlElement x=xmldoc.CreateElement("Root");

           

           XmlElement newjob = xmldoc.CreateElement("jobs"); // parent

           XmlElement jobid = xmldoc.CreateElement("job_ids");

           jobid.InnerText = txtJobid.Text;           

           XmlElement jobname = xmldoc.CreateElement("job_desc");

           jobname.InnerText = txtJobdesc.Text;

           XmlElement minsal = xmldoc.CreateElement("min_lvl");

           minsal.InnerText = txtminlvl.Text;

           XmlElement maxsal = xmldoc.CreateElement("max_lvl");

           maxsal.InnerText = txtmaxlvl.Text;

           newjob.AppendChild(jobid);

           newjob.AppendChild(jobname);

           newjob.AppendChild(minsal);

           newjob.AppendChild(maxsal);

           x.AppendChild(newjob);

           xmldoc.AppendChild(x);   // End the Root.                                          

           xmldoc.Save("C:\\jobs12345.xml");     // the the xml file to disk

           Label1.Text = "create xml document programmatically...";

How to add Attributes to xmlElements?

For adding Attributes to XmlElement we have a class is XmlAttribute class.

Ex:

Prepare xml document programmatic along with Attributes:

XmlDocument myDoc = new XmlDocument();

myDoc.AppendChild(myDoc.CreateXmlDeclaration("1.0", "utf-8", "yes"));

            //The Father

            XmlElement Father = myDoc.CreateElement("Father");

            //Create attributes

            XmlAttribute FatherName = myDoc.CreateAttribute("Name");

            XmlAttribute FatherAge = myDoc.CreateAttribute("Age");

            //Add values to attributes

            FatherName.Value = "My father";

            FatherAge.Value = "65";

            //Append attributes to their correspondent element

            Father.Attributes.Append(FatherName);

            Father.Attributes.Append(FatherAge);

            //Add the element to the Familie node

            Familie.AppendChild(Father);

            //The mother

            XmlElement Mother = myDoc.CreateElement("Mother");

            //Create attributes

            XmlAttribute MotherName = myDoc.CreateAttribute("Name");

            XmlAttribute MotherAge = myDoc.CreateAttribute("Age");

            //Add values to attributes

            MotherName.Value = "My mother";

            MotherAge.Value = "60";

            //Append attributes to their correspondent element

            Mother.Attributes.Append(MotherName);

            Mother.Attributes.Append(MotherAge);

            //Add the element to the Familie node

            Familie.AppendChild(Mother);

            //The sister

            XmlElement Sister = myDoc.CreateElement("Sister");

            //Create attributes

            XmlAttribute SisterName = myDoc.CreateAttribute("Name");

            XmlAttribute SisterAge = myDoc.CreateAttribute("Age");

            //Add values to attributes

            SisterName.Value = "My sister";

            SisterAge.Value = "20";

            //Append attributes to their correspondent element

            Sister.Attributes.Append(SisterName);

            Sister.Attributes.Append(SisterAge);

            //Add the element to the Familie node

            Familie.AppendChild(Sister);

            //The brother

            XmlElement Brother = myDoc.CreateElement("Brother");

            //Create attributes

            XmlAttribute BrotherName = myDoc.CreateAttribute("Name");

            XmlAttribute BrotherAge = myDoc.CreateAttribute("Age");

            //Add values to attributes

            BrotherName.Value = "My brother";

            BrotherAge.Value = "21";

            //Append attributes to their correspondent element

            Brother.Attributes.Append(BrotherName);

            Brother.Attributes.Append(BrotherAge);

            //Add the element to the Familie node

            Familie.AppendChild(Brother);

            //wrapp all elements nodes in wrapper node

myDoc.AppendChild(Familie);               myDoc.Save(@"C:\myFamilssie.xml");            Console.WriteLine("Document is generated successfully!!");

Note: Don’t write XmlAttributes for declaration of xml document .to specify declaration we have

XmlDocument myDoc = new XmlDocument();

myDoc.AppendChild(myDoc.CreateXmlDeclaration("1.0", "utf-8", "yes"));

****

How to Add new Elements to Existing Xml Documents?

    How to add new Element to existing xml document?

           XmlDocument xmldoc = new XmlDocument();

           xmldoc.Load("C:\\jobs.xml");   // Loading xml file to memory

          

           XmlElement newjob = xmldoc.CreateElement("jobs"); // parent

           XmlElement jobid = xmldoc.CreateElement("job_ids");

           jobid.InnerText = txtJobid.Text;

           XmlElement jobname = xmldoc.CreateElement("job_desc");

           jobname.InnerText = txtJobdesc.Text;

           XmlElement minsal = xmldoc.CreateElement("min_lvl");

           minsal.InnerText = txtminlvl.Text;

           XmlElement maxsal = xmldoc.CreateElement("max_lvl");

           maxsal.InnerText = txtmaxlvl.Text;

           newjob.AppendChild(jobid);

           newjob.AppendChild(jobname);

           newjob.AppendChild(minsal);

           newjob.AppendChild(maxsal);

           xmldoc.DocumentElement.AppendChild(newjob);

           Label1.Text = "dadasdlfkjaskld";

           xmldoc.Save("C:\\jobs.xml");     // the the xml file to disk

            

How to working with xml in .net?

XmlDocument and XmlDataDocument are a classes which is used to work with xml doucments in the form of memory objects.

XmlDocument:

xmlDocument is an in-memory object which loads the entire document into memory then perform the requried operations.

How to Load an xml file to XmlDocument Class?

XmlDocument loads the xml file as a in-memory.to load the xml file to in memory this object has 2 ways

1.  Load(string filename)

2.  LoadXml(“<book><id>1</id></book>”);

Class Declaration:

XmlDocument xmldoc;      XmlNode n;

Under Load Button

xmldoc = new XmlDocument();

            xmldoc.Load(textBox1.Text);

         

Then xmlDocument load the data. As in MEMORY.

Then Find the data.now data is available as IN-MEMORY.

Then we have 2 methods to pointing a particular elements in the xml document using xpath so we have 2 methods like

SingleNodes

SelectSinglNode accepts xpath query to retrive particular data to memory.

Like

private void Find(object sender, EventArgs e)

{         

           n = xmldoc.SelectSingleNode(@"/NewDataSet/jobs[job_id="+Convert.ToInt32(textBox6.Text)+"]");                       

            if(n!=null)

            {                  

                    textBox2.Text=n.ChildNodes[0].InnerText;

                    textBox3.Text=n.ChildNodes[1].InnerText;

                    textBox4.Text=n.ChildNodes[2].InnerText;

                    textBox5.Text=n.ChildNodes[3].InnerText;

            }

            else

                MessageBox.Show("absent today");

        }

Now here n pointing particular data.

How to retrive data of a particular Element ?

Under GetNames

private void GetNames(object sender, EventArgs e)

{

            listBox1.Items.Clear();

             XmlNodeList nl=xmldoc.GetElementsByTagName("job_desc");

           

                foreach (XmlNode n in nl)

                {

                    listBox1.Items.Add(n.InnerText);

                   

                }  

}

How to   save   the data after modifications in xml file(document)?

private void save(object sender, EventArgs e)

        {// after n is find, then n----->pointing to a node save modification of THAT** childnods is possible.

            n.ChildNodes[1].InnerText = textBox3.Text;

            n.ChildNodes[2].InnerText = textBox4.Text;

            n.ChildNodes[3].InnerText = textBox5.Text;

            MessageBox.Show("Data Modified");

          xmldoc.Save(textBox1.Text);

            GetNames(sender, e);

        }

How to Delete the data from the xml document?

private void Delete(object sender, EventArgs e)

{

          xmldoc.DocumentElement.RemoveChild(n);            

            xmldoc.Save(textBox1.Text);

            GetNames(sender, e);

}

How ways we can work with xml documents?

In .net we can work with xml files(documents) in 2 ways.

1.       Stream Model

2.       DOM Model(Documents Object model)

Stream Model:

In order to work with stream model we have to import a namespace

using System.Xml;

XmlReader,xmlWrtier are base classes to with xml files.and perform the the basic operations also.

Base Classes

XmlReader----xmlTextReader

XmlWriter----xmlTextWriter are derived classes.to read and write xml documents.

How to Read an xml file in .net?

using System.Xml;

we have an xml file in our drive as a physically like c:\\jobs.xml

Now I want to read that xml file so we have to use object of xmlTextReader.

EX:

Under ButtonClick:

XmlReader/XmlTextReader xtr = new XmlTextReader("C:\\jobs.xml");

while(xtr.Read())

{

if (xtr.NodeType == XmlNodeType.Element && xtr.Name == "job_desc")

{

xtr.Read();

ListBox1.Items.Add(xtr.Value.ToString());

}

}

How to Write an xml doucment to Physically?

Take Controls: TextBox1,TextBox2,CheckBox1,Button1 controls

Under the ButtonClick

XmlWriter/XmlTextWriter xmlw= new XmlTextWriter(@"c:\status.xml", null);

            xmlw.WriteStartDocument();

            xmlw.WriteStartElement("Roots");

            xmlw.WriteStartElement("tasks");

            xmlw.WriteElementString("programmid", TextBox1.Text);

            xmlw.WriteElementString("task", TextBox2.Text);

   if (CheckBox1.Checked)

   {

                xmlw.WriteElementString("status", "completed");

   }

  else

   xmlw.WriteElementString("status", "incompleted");

        //    xmlw.WriteEndElement();

//  buffer is fill automatically data moves to physical file             

         

  xmlw.WriteEndElement();

  xmlw.Flush();

  xmlw.Close();           

  Label1.Text = "Data is saved Succefully...";