Display SubTotal and Grand Total Year wise using C#  in ASP.Net

HTML

<div>
<asp:GridView ID="gvData" AutoGenerateColumns="false"
OnDataBound="OnDataBound" OnRowCreated="OnRowCreated"

        runat="server">

        <Columns>

       <asp:BoundField HeaderText="District" DataField="District" />

       <asp:BoundField HeaderText="Year" DataField="Year" />

       <asp:BoundField HeaderText="Total Works" DataField="Total Works" />

       <asp:BoundField HeaderText="Completed" DataField="Completed" />

        </Columns>

    </asp:GridView>

</div>

C#

protected void Page_Load(object sender, EventArgs e)

{

    if (!IsPostBack)

    {

        DataTable dt = new DataTable();

        dt.Columns.AddRange(new DataColumn[] {

            new DataColumn("District")

        ,new DataColumn("Year")

        ,new DataColumn("Total Works")

        ,new DataColumn("Completed")

        });

        dt.Rows.Add("Delhi", "2013-14", "72", "72");

        dt.Rows.Add("Bihar", "2013-14", "57", "57");

        dt.Rows.Add("UP", "2013-14", "200", "200");

        dt.Rows.Add("Andhra Pradesh", "2013-14", "100", "100");

        dt.Rows.Add("Chandigarh", "2013-14", "82", "77");

        dt.Rows.Add("Goa", "2013-14", "81", "81");

        dt.Rows.Add("Gujrat", "2014-15", "225", "218");

        dt.Rows.Add("Haryana", "2014-15", "162", "156");

        dt.Rows.Add("Kerala", "2014-15", "573", "485");

        dt.Rows.Add("Maharashtra", "2014-15", "261", "249");

        dt.Rows.Add("Ranchi", "2014-15", "173", "107");

        dt.Rows.Add("Tripura", "2014-15", "248", "201");

        gvData.DataSource = dt;

        gvData.DataBind();

    }

}

     

string currentYear = string.Empty;

int subTotal = 0;

int total = 0;

int subTotalRowIndex = 0;

protected void OnRowCreated(object sender, GridViewRowEventArgs e)

{

    subTotal = 0;

    if (e.Row.RowType == DataControlRowType.DataRow)

    {

        DataTable dt = (e.Row.DataItem as DataRowView).DataView.Table;

        string year = dt.Rows[e.Row.RowIndex]["year"].ToString();

        total += Convert.ToInt32(dt.Rows[e.Row.RowIndex]["Total Works"]);

        if (year != currentYear)

        {

            if (e.Row.RowIndex > 0)

            {

                for (int i = subTotalRowIndex; i < e.Row.RowIndex; i++)

                {

                    subTotal += Convert.ToInt32(gvData.Rows[i].Cells[2].Text);

                }

                this.AddTotalRow("Sub Total", subTotal.ToString("N2"));

                subTotalRowIndex = e.Row.RowIndex;

            }

            currentYear = year;

        }

    }

}

private void AddTotalRow(string labelText, string value)

{

    GridViewRow row = new GridViewRow(0, 0, DataControlRowType.DataRow, 
DataControlRowState.Normal);

    row.BackColor = ColorTranslator.FromHtml("#F9F9F9");

    row.Cells.AddRange(new TableCell[3] { new TableCell (), //Empty Cell

    new TableCell { Text = labelText, HorizontalAlign = HorizontalAlign.Right},

    new TableCell { Text = value, HorizontalAlign = HorizontalAlign.Right } });

    gvData.Controls[0].Controls.Add(row);

}

     

protected void OnDataBound(object sender, EventArgs e)

{

    for (int i = subTotalRowIndex; i < gvData.Rows.Count; i++)

    {

        subTotal += Convert.ToInt32(gvData.Rows[i].Cells[2].Text);

    }

    this.AddTotalRow("Sub Total", subTotal.ToString("N2"));

    this.AddTotalRow("Total", total.ToString("N2"));

}