protected void Button1_Click(object sender, EventArgs e)
        {
            SqlConnection sc = new SqlConnection(@"Data Source=DESKTOP-CKK6JR1;Initial Catalog=Tmu_login;Integrated Security=True");

            sc.Open();
            var            test           = DropDownList1.SelectedValue;
            var            test1          = TextBox1.ToString();
            var            test2          = TextBox2.ToString();
            string         selectedValue  = (this.DropDownList1.SelectedValue);
            string         selectedValue1 = (this.TextBox1.Text);
            string         selectedValue2 = (this.TextBox2.Text);
            SqlDataAdapter sd             = new SqlDataAdapter("select * from attendencestatus where emp_id =" + "'" + selectedValue + "'", sc);
            //
            DataSet ds = new DataSet();

            sd.Fill(ds, "attendencestatus");
            GridView1.DataSource = ds.Tables[0];
            GridView1.DataBind();
            sc.Close();
            DropDownList1.DataTextField  = "emp_id";
            DropDownList1.DataValueField = "emp_id";
        }