converting from Datagrid to xml

Coding :


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Data;
using System.Data.SqlClient;
namespace sample
{
///

/// Interaction logic for Window1.xaml
///

public partial class Window1 : Window
{
SqlConnection con = new SqlConnection("server=.;database=test;trusted_connection=true;");
public Window1()
{
InitializeComponent();
}

private void Window_Loaded(object sender, RoutedEventArgs e)
{
con.Open();
comboBox1.Items.Add("All");
comboBox2.Items.Add("All");
comboBox3.Items.Add("All");
comboBox4.Items.Add("All");
comboBox1.SelectedIndex = 0;
comboBox2.SelectedIndex = 0;
comboBox3.SelectedIndex = 0;
comboBox4.SelectedIndex = 0;
SqlCommand cmd = new SqlCommand("select distinct gn from test", con);
SqlDataReader rd = cmd.ExecuteReader();
while (rd.Read())
{
comboBox1.Items.Add(rd[0].ToString());
}
rd.Close();
cmd = new SqlCommand("select distinct cn from test", con);
rd = cmd.ExecuteReader();
while (rd.Read())
{
comboBox2.Items.Add(rd[0].ToString());
}

rd.Close();
cmd = new SqlCommand("select distinct at from test", con);
rd = cmd.ExecuteReader();
while (rd.Read())
{
comboBox3.Items.Add(rd[0].ToString());
}
rd.Close();
cmd = new SqlCommand("select distinct ft from test", con);
rd = cmd.ExecuteReader();
while (rd.Read())
{
comboBox4.Items.Add(rd[0].ToString());
}
rd.Close();
con.Close();
}

private void button2_Click(object sender, RoutedEventArgs e)
{
int i = 0;
string com = "select * from test";
if (comboBox1.Text != "All" || comboBox2.Text != "All" || comboBox3.Text != "All" || comboBox4.Text != "All")
{
com += " where ";
}
if (comboBox1.Text != "All")
{
if (i < 1)
{
com += "gn='" + comboBox1.Text + "' ";
i++;
}
else
{
com += "and gn='" + comboBox1.Text + "' ";
i++;
}
}
if (comboBox2.Text != "All")
{
if (i < 1)
{
com += "cn='" + comboBox2.Text + "' ";
i++;
}
else
{
com += "and cn='" + comboBox2.Text + "' ";
i++;
}
}
if (comboBox3.Text != "All")
{
if (i < 1)
{
com += "at='" + comboBox3.Text + "' ";
i++;
}
else
{
com += "and at='" + comboBox3.Text + "' ";
i++;
}
}
if (comboBox4.Text != "All")
{
if (i < 1)
{
com += "ft='" + comboBox4.Text + "' ";
i++;
}
else
{
com += "and ft='" + comboBox4.Text + "' ";
i++;
}
}
DataTable datatable = new DataTable();
datatable.Columns.Add("Select", typeof(bool));
datatable.Columns.Add("Group Name", typeof(string));
datatable.Columns.Add("Client Name", typeof(string));
datatable.Columns.Add("Assesment Type", typeof(string));
datatable.Columns.Add("Form Type", typeof(string));

con.Open();
SqlCommand cmd = new SqlCommand(com,con);
SqlDataReader rd = cmd.ExecuteReader();
while (rd.Read())
{
DataRow tr = datatable.NewRow();
tr["Select"] = false;
tr["Group Name"] = rd[0].ToString();
tr["Client Name"] = rd[1].ToString();
tr["Assesment Type"] = rd[2].ToString();
tr["Form Type"] = rd[3].ToString();
datatable.Rows.Add(tr);
}
rd.Close();
con.Close();
dataGrid1.DataContext = datatable;
}

private void button1_Click(object sender, RoutedEventArgs e)
{
String str = "" + Environment.NewLine + "<node>" + Environment.NewLine;
for (int i = 0; i < dataGrid1.Items.Count; i++)
{
System.Data.DataRowView dv = (DataRowView)dataGrid1.Items[i];
DataRow dr = dv.Row;
if(dr.ItemArray[0].ToString()=="True")
{
str += "<record>" + Environment.NewLine;
str += "<" + dataGrid1.Columns[1].Header.ToString().Replace(" ", "_") + ">" + Environment.NewLine + dr.ItemArray[1].ToString() + Environment.NewLine + " + Environment.NewLine;
str += "<" + dataGrid1.Columns[2].Header.ToString().Replace(" ", "_") + ">" + Environment.NewLine + dr.ItemArray[2].ToString() + Environment.NewLine + " + Environment.NewLine;
str += "<" + dataGrid1.Columns[3].Header.ToString().Replace(" ", "_") + ">" + Environment.NewLine + dr.ItemArray[3].ToString() + Environment.NewLine + " + Environment.NewLine;
str += "<" + dataGrid1.Columns[4].Header.ToString().Replace(" ", "_") + ">" + Environment.NewLine + dr.ItemArray[4].ToString() + Environment.NewLine + " + Environment.NewLine;
str += "" + Environment.NewLine;
}
}
str += "";
System.IO.File.WriteAllText("G:\\text.xml", str);
MessageBox.Show("File Generated Successfully");
}
}
}