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[C# Programming]

public partial class Default2 : System.Web.UI.Page
{
SqlConnection cnx = new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|Coupon Management.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");
SqlDataAdapter da1 = new SqlDataAdapter();
DataSet ds = new DataSet();
SqlCommand cmd = new SqlCommand();
DataTable dataTable;

protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{

FillVendorGrid();

}
}

private void FillVendorGrid()
{

dataTable = new DataTable();

cmd.Connection = cnx;


cmd.CommandText = "SELECT Coupon_Info.RecievingDate, CouponType.CouponName, Coupon_Info.Serial_Start, Coupon_Info.Serial_End, Coupon_Info.Recieved_By FROM Coupon_Info INNER JOIN CouponType ON Coupon_Info.Coupon_TypeID = CouponType.CouponTypeID";

da1 = new SqlDataAdapter(cmd);

da1.Fill(dataTable);
GridView1.DataSource = dataTable;
GridView1.DataSource = ds;
GridView1.DataSourceID = String.Empty;

//GridView1.DataBind();
// GridView1.DataSource = ds;
// GridView1.DataBind();

}
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{

GridView1.PageIndex = e.NewPageIndex;

FillVendorGrid();

}
protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
{

cmd.Connection = cnx;

cmd.CommandText = "DELETE FROM Coupon_Info WHERE RecievingDate='" + GridView1.DataKeys[e.RowIndex].Values[0].ToString() + "'";

cnx.Open();

cmd.ExecuteNonQuery();

cnx.Close();

FillVendorGrid();

}
}