public void add()
    {
        DataTable  dt  = new DataTable();
        DataColumn dc1 = new DataColumn("Vacancy Id");

        dt.Columns.Add(dc1);
        DataColumn dc2 = new DataColumn("Number of Positions");

        dt.Columns.Add(dc2);
        DataColumn dc3 = new DataColumn("Required Date");

        dt.Columns.Add(dc3);
        DataColumn dc4 = new DataColumn("Skills");

        dt.Columns.Add(dc4);
        DataColumn dc = new DataColumn("Domain");

        dt.Columns.Add(dc);
        DataColumn dc6 = new DataColumn("Experience");

        dt.Columns.Add(dc6);
        DataColumn dc7 = new DataColumn("Loctaion");

        dt.Columns.Add(dc7);
        DataColumn dc8 = new DataColumn("Status");

        dt.Columns.Add(dc8);

        List <IVacancy> vacancyList = vacancyManager.SelectVacancy((int)Session["empid"]);

        if (vacancyList.Count != 0)
        {
            Error.Visible = false;
            foreach (IVacancy vacancy in vacancyList)
            {
                DataRow dr = dt.NewRow();
                dr["Vacancy Id"]          = vacancy.VacancyID;
                dr["Number of Positions"] = vacancy.NoOfPositions;
                dr["Required Date"]       = vacancy.RequiredDate;
                dr["Skills"]     = vacancy.Skills;
                dr["Domain"]     = vacancy.Domain;
                dr["Experience"] = vacancy.Experience;
                dr["Loctaion"]   = vacancy.Location;
                dr["Status"]     = vacancy.Status;
                dt.Rows.Add(dr);
            }
            GridView1.DataSource = dt;
            GridView1.DataBind();
        }
        else
        {
            Error.Visible = true;
        }
    }