how to set check box in header and rows in datagrid in wpf

hi,

    I have problem to design datagrid with checkbox in wpf and also how to get only checked values from datagrid to backend(c#).....

my XAML coding..

<UserControl x:Class="wpfpayroll.payslip"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:grid="http://schemas.microsoft.com/wpf/2008/toolkit"
             mc:Ignorable="d"
             d:DesignHeight="482" d:DesignWidth="912" Loaded="UserControl_Loaded">
    


    <Grid >
        <GroupBox Header="Payslip Details" Name="lvpayslipdetails" Margin="0,66,0,36">
            <grid:DataGrid x:Name="lvpayslip" x:Uid="MyDataGrid" AutoGenerateColumns="False"
AlternationCount="1" SelectionMode="Single" ItemsSource="{Binding Path=Table}" IsReadOnly="True" HeadersVisibility="Column" FontSize="14" >

                <grid:DataGrid.Columns>

                    <grid:DataGridTemplateColumn>
                        <grid:DataGridTemplateColumn.Header>
                            <CheckBox Content="Discontinue All" Click="CheckBox_Click" />
                        </grid:DataGridTemplateColumn.Header>
                        <grid:DataGridTemplateColumn.CellTemplate>
                            <DataTemplate>
                                <CheckBox Name="chkDiscontinue" IsChecked="{Binding Path=Discontinue,Mode=TwoWay}" Margin="45 2 0 0" Click="chkDiscontinue_Click" />
                            </DataTemplate>
                        </grid:DataGridTemplateColumn.CellTemplate>
                    </grid:DataGridTemplateColumn>
                    <grid:DataGridTextColumn Binding="{Binding Path=p_id}" IsReadOnly="True"
Header="P.Id" Width="0.7*" />

                    <grid:DataGridTextColumn Binding="{Binding Path=dbempname}"
Header="Emp Name" Width="2*" IsReadOnly="True" />
                    <grid:DataGridTextColumn Binding="{Binding Path=pmonth}"
Header="Month" Width="0.9*" IsReadOnly="True" />
                    <grid:DataGridTextColumn Binding="{Binding Path=pyear}"
Header="Year" Width="0.5*" IsReadOnly="True" />
  <grid:DataGridTextColumn Binding="{Binding Path=deduction,StringFormat=0.00}"
Header="Deduction" Width="1.5*" IsReadOnly="True" />

                    <grid:DataGridTextColumn Binding="{Binding Path=netpay,StringFormat=0.00}"
Header="Net Pay" Width="1.3*" IsReadOnly="True" />

                   
                </grid:DataGrid.Columns>

            </grid:DataGrid>

        </GroupBox>
    </Grid>
</UserControl>

and C# coding...

public payslip()
        {
            InitializeComponent();
        }

        SqlConnection con;
        public bool flag;
        string cn = ConfigurationManager.AppSettings["cc"];

        public void viewleave()
        {
            con = new SqlConnection(cn);
            con.Open();
            SqlCommand cmd = new SqlCommand("lvpayslip", con);
            cmd.CommandType = CommandType.StoredProcedure;
            DataTable dt = new DataTable();
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            da.Fill(dt);
            lvpayslip.DataContext = dt.DefaultView;
            con.Close();
        }

        private void UserControl_Loaded(object sender, RoutedEventArgs e)
        {
            viewleave();
        }

       
        
        
            }
        }
 then i wanna checkbox columns like that please help me.....