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Create a Xml File using XMLDom need auto increment attribute.

Hi ,
I have a Form in c# with fields which take following input
employeename
employeedescription
employeelocation
employeestartdate
employeeenddate
employeeemail

When i fill in the form and submit it write a xml file and appends new data...
But i want to add a attribute to employee as id which will auto increment by 1 when the form is submitted each time.

i have the following code....can you make changes to get it working with autoincrement id?
Pls help me with autoincrementing an attribute named "id" for employee

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Xml;
using System.IO;

public partial class inserteventbyxml : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }


    protected void button1_Click(object sender, EventArgs e)
    {
        string filename = Request.PhysicalApplicationPath + @"employees.xml";
        XmlDocument doc = new XmlDocument();
        if (File.Exists(filename))
        {
            doc.Load(filename);
        }
        else
        {
          XmlElement mainelement= doc.CreateElement("employees");   
  doc.AppendChild(mainelement);


        }
        XmlElement root = doc.DocumentElement;

        XmlElement nextroot= doc.CreateElement("employee");
        XmlElement employeenameelement = doc.CreateElement("employeename");
        XmlElement employeedescriptionelement = doc.CreateElement("employeedescription");
        XmlElement employeelocationelement = doc.CreateElement("employeelocation");
        XmlElement employeestartelement = doc.CreateElement("employeestart");
        XmlElement employeeendelement = doc.CreateElement("employeeend");
        XmlElement employeeemailelement = doc.CreateElement("employeeemail");



        nextroot.AppendChild(employeenameelement );
        employeenameelement .InnerText = textmployeename.Text;
        nextroot.AppendChild(employeedescriptionelement);
        employeedescriptionelement.InnerText = textemployeedescription.Text;
        nextroot.AppendChild(employeelocationelement);
        employeelocationelement.InnerText = textemployeelocation.Text;
        nextroot.AppendChild(employeestartelement);
        employeestartelement.InnerText = textemployeestart.Text;
        nextroot.AppendChild(employeeendelement);
        employeeendelement.InnerText = textemployeeend.Text;
        nextroot.AppendChild(employeeemailelement);
        employeeemailelement.InnerText = textemployeeemail.Text;

        root.AppendChild(nextroot);

        doc.Save(filename);
        lblresult.Text = "employee added";
        
    }
}

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Thank you so much

jjardine

If the document already exists, try using xpath to grab the last Employee element with something like this:

/employees/employee[last()]

Once you use that expression to get the last employee you can grab the attribute value then increment it by one.

Here is a MSDN reference for using Xpath with .net. http://support.microsoft.com/kb/308333

seetoronto

ASKER

would you mind to code it for me to show a perfect working thing.
I am absolutely new to xml, xpath, and .Net
I am learning......

anticipating a early reply with code.

Mlanda T

try this:

long newId = 0;

if (File.Exists(filename))
{
	doc.Load(filename);
	XmlNode lstNode = xmlDoc.SelectSingleNode("//employee/person[last()]");
	newId = lstNode.Attributes("id").Value as long;
}
else
{
	XmlElement mainelement= doc.CreateElement("employees");  
	doc.AppendChild(mainelement);
}

XmlElement root = doc.DocumentElement;

XmlElement nextroot= doc.CreateElement("employee");
nextroot.Attributes("id") = newId + 1;

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seetoronto

ASKER

I am afarid but this does not work...Probably the Syntax is the problem...
Could you try this on your pc if it works ??
I will appreciate a working code.

thx

ASKER CERTIFIED SOLUTION

Mlanda T

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seetoronto

ASKER

Thank you so much... Your code worked just PERFECT, and you were so quick...
I highly appreciate....
I have another question related to similar xml file..
Can you pls see my another posted question as below?
My posted question is Searching a XML file and displaying results in GridView.
Hope you can solve this too....

Thx a mil

seetoronto

ASKER

Very good. Just as i needed.
I can say EE is the best community as they have great talented Gurus..

thx again