获取请求的页的 HttpRequest 对象。
一、HttpRequest 类
使 ASP.NET 能够读取客户端在 Web 请求期间发送的 HTTP 值。
下面的代码示例使用 StreamWriter 类将若干 HttpRequest 类属性值的值写入文件。对于是字符串类型的属性，属性值被写入文件时将被编码为 HTML。表示集合的属性会被依次通过，而这些属性包含的各个键/值对都会被写入该文件。
<%@ Page Language="C#" %>
<%@ import Namespace="System.Threading" %>
<%@ import Namespace="System.IO" %>
<script runat="server">
/* NOTE: To use this sample, create a c:\temp\CS folder,
* add the ASP.NET account (in IIS 5.x <machinename>\ASPNET,
* in IIS 6.x NETWORK SERVICE), and give it write permissions
* to the folder.*/
private const string INFO_DIR = @"c:\temp\CS\RequestDetails";
public static int requestCount;
private void Page_Load(object sender, System.EventArgs e)
{
// Create a variable to use when iterating
// through the UserLanguages property.
int langCount;
int requestNumber = Interlocked.Increment(ref requestCount);
// Create the file to contain information about the request.
string strFilePath = INFO_DIR + requestNumber.ToString() + @".txt";
StreamWriter sw = File.CreateText(strFilePath);
try
{
// Write request information to the file with HTML encoding.
&nbs
设置下拉框的初始值：
<asp:DropDownList ID="DropDownList1" runat="server">
<asp:ListItem Text="小学" Value="1"></asp:ListItem>
<asp:ListItem Text="中学" Value="2"></asp:ListItem& ......
