create a xml

[BATISTA]

Hi
I have did a program such that , i will have two text box name and age in my
form..and a button named save. so that when the values entered r in the text
box..a xml file is created with those data...
Now I can able to create one set of values…. No what I need is that when
again some other value is entered in the textbox. It should also be written
in the xml file..but without deleting the other. I mean it should append on
the other..

For example: first I entered forst as john and 22 for name and age ..it will
added in the xml file..no again if I enter charu and 23 as name and age..
Now xml should have john and 22 as well as charu and 23…

And also one more thing is that if I again enter John. It should give a
message that it has already been entered. No values should be repeated again.
Please help me to do this…..

The coding which I did is as follows.

In side the button click
//save Button
private void button1_Click(object sender, System.EventArgs e)
{
DataSet dataSet = new DataSet();
//read the schema
dataSet.ReadXmlSchema("..\\..\\PlaygroMenu.xsd");
//create a new row
DataRow oValues;
oValues = dataSet.Tables[0].NewRow();
//enter the values
oValues[0] = txtName.Text;
oValues[1] = Convert.ToInt32(txtAage.Text);

//check for duplication
bool hasalready = false;
foreach(DataRow row in dataSet.Tables[0].Rows)
{
if(row.ItemArray[0].ToString().Equals(txtID.Text))
{
hasalready = true;
}
}
//
if(!hasalready)
{
//add the row to the dataset
dataSet.Tables[0].Rows.Add(oValues);
//write the data to a xml file
dataSet.WriteXml("..\\..\\resultdata.xml", XmlWriteMode.WriteSchema);
MessageBox.Show("Saved");
}

else
{
MessageBox.Show("Already Exists");
}

}


private void Form1_Load(object sender, System.EventArgs e)
{
DataSet dataSet = new DataSet();
//read the schema
dataSet.ReadXmlSchema("..\\..\\Menu.xsd");

System.IO.FileInfo file = new System.IO.FileInfo("..\\..\\mydata.xml");

//check whethere there is result xml file...
if (file.Exists)
{
dataSet.ReadXml("..\\..\\resultdata.xml");
}

}


Please help me to do this..

Batista