Forms Data Controls :: How To Display Data In Griview On Page Load

I have made sample code to display data in griview on page load. Evrything is wrkng without error but my page is coming blank as no data is shown

Code:

// Class Database for various methods
public class TestClass
{
private string cnstr = ConfigurationManager.ConnectionStrings["test"].ConnectionString;
private string sql="";
public DataTable Fetch()
{
string sql = "select * from item";
SqlDataAdapter da = new SqlDataAdapter(sql, cnstr);
DataTable dt = new DataTable();
da.Fill(dt);
return dt;
}
}
//Code Behind in Web Page. gdv1 name given to gridview
public partial class _Default : System.Web.UI.Page
{
TestClass tcls = new TestClass();
protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostBack)
{
FiillItemInGrid();
}
}
private void FiillItemInGrid()
{
DataTable dtitem = tcls.Fetch();
if (dtitem.Rows.Count > 0)
{
gdv1.DataSource = dtitem;
gdv1.DataBind();
gdv1.Visible = true;
}
else
{
dtitem.Rows.Add(dtitem.NewRow());
gdv1.DataSource = dtitem;
gdv1.DataBind();
int totalcolums = gdv1.Rows[0].Cells.Count;
gdv1.Rows[0].Cells.Clear();
gdv1.Rows[0].Cells.Add(new TableCell());
gdv1.Rows[0].Cells[0].ColumnSpan = totalcolums;
gdv1.Rows[0].Cells[0].Text = "No Record Found";
}
}
}

Working in this way still no data is populated.