Dropdownlist添加一项——"请选择"

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

          this.drpDownDepartment.Items.Insert(0, new ListItem("请选择部门", "0"));

        }

在调用的时候，需要做一个判断:

            if (this.drpDownDepartment.SelectedItem.Text != "请选择部门......")
            {
                StaffBLL.UpdateStaffDepIDByID(this.lblNum.Text, departmentID);
            }