01.using System;
02.using System.Collections;
03.using System.Configuration;
04.using System.Data;
05.using System.Linq;
06.using System.Web;
07.using System.Web.Security;
08.using System.Web.UI;
09.using System.Web.UI.HtmlControls;
10.using System.Web.UI.WebControls;
11.using System.Web.UI.WebControls.WebParts;
12.using System.Xml.Linq;
13.
14.
15.namespace Test
16.{
17. public partial class WebForm2 : System.Web.UI.Page
18. {
19. protected void Page_Load(object sender, EventArgs e)
20. {
21.
22.
23.
24. }
25.
26. protected void bt1_Click(object sender, EventArgs e)
27. {
28.
29. }
30.
31. protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
32. {
33. if (DropDownList1.SelectedValue == "0")
34. {
35. DropDownList2.Items.Clear();
36. DropDownList2.Items.Add(new ListItem("เชียงใหม่", "0"));
37. DropDownList2.Items.Add(new ListItem("เชียงราย", "0"));
38. DropDownList2.Items.Add(new ListItem("เชียงแม่ฮ่องสอน", "0"));
39.
40. }
41. else if (DropDownList1.SelectedValue == "1")
42. {
43. DropDownList2.Items.Clear();
44. DropDownList2.Items.Add(new ListItem("ชุมพร", "0"));
45. DropDownList2.Items.Add(new ListItem("หาดใหญ่", "0"));
46. DropDownList2.Items.Add(new ListItem("สงขลา", "0"));
47.
48. }
49. la1.Text = DropDownList1.SelectedItem.Text;
50. la2.Text = DropDownList2.SelectedItem.Text;
51.
52.
53. }
54.
55. }
56.}
