void BindData()
{
ClassGradCountry gc = new ClassGradCountry();
DataTable dt = gc.GetGradCountry("", "", "");
GridView1.DataSource = dt;
GridView1.DataBind();
SetViewState(dt);
}
protected void btnSearchRefresh_Click(object sender, EventArgs e)
{
ClearData();
ClassGradCountry cg = new ClassGradCountry();
DataTable dt = cg.GetGradCountry("", "", "");
GridView1.DataSource = dt;
GridView1.DataBind();
SetViewState(dt);
}