技术资料 > .Net专区 > 面向对象程序基础 : 从一个舆论调查的制作谈面向对象的编程思路（五）

从一个舆论调查的制作谈面向对象的编程思路（五）

March 25,2004

好了，现在万事俱备，只欠东风了，让我们看看现在做一个舆论调查多么简单：

file : vote.aspx

<%@ Page language="c#" Codebehind="vote.cs" AutoEventWireup="false" Inherits="Football.vote" %>

<html>
  <head>
  <title>532.com.cn --- 舆论调查 ---</title>
  <link rel="stylesheet" href="style/style.css" type="text/css">

  </head>
  <body>

<form method="post" runat="server">
<table width=400 height=300 align=center>
   <tr>
      <td class=cn valign=top align=center><b>调查题目：
         <asp:label id="lblSurveyTitle" runat=Server class=cn></asp:label>
      </td>
   </tr>
   <tr>
      <td alin=center>
         <asp:image id="imgSurvey" runat=Server></asp:image>
      </td>
   </tr>
   <tr>
      <td align=center>
      <input type=button onclick="window.close();" value="关闭此窗口">
      </td>
   </tr>
</table>
   </form>

  </body>
</html>

file: vote.cs
namespace Football
{
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;

/// <summary>
/// Summary description for vote.
/// </summary>
public class vote : System.Web.UI.Page
{
      protected System.Web.UI.WebControls.Image imgSurvey;
      protected System.Web.UI.WebControls.Label lblSurveyTitle;

      private string m_strSurveyID ;
      private int m_intVoteID ;
      public vote()
      {
         Page.Init += new System.EventHandler(Page_Init);
      }

      protected void Page_Load(object sender, EventArgs e)
      {
         if (!IsPostBack)
         {
            //
            // Evals true first time browser hits the page
            //
         }
      }

      protected void Page_Init(object sender, EventArgs e)
      {
         //
         // CODEGEN: This call is required by the ASP+ Windows Form Designer.
         //
         InitializeComponent();
         Init() ;
      }

      /// <summary>
      /// Required method for Designer support - do not modify
      /// the contents of this method with the code editor.
      /// </summary>
      private void InitializeComponent()
      {
         this.Load += new System.EventHandler (this.Page_Load);
      }

      private void Init()
      {
         m_strSurveyID = Request["surveyid"].ToString() ;
         FootballSurvey mySurvey = new FootballSurvey() ;

         try
         {
            m_intVoteID = Request["vote"].ToInt32() ;
            mySurvey.LoadFromDatabase(m_strSurveyID) ;
            lblSurveyTitle.Text = mySurvey.Title ;
            if (m_intVoteID < mySurvey.Items.Count)
            {
                  mySurvey.Vote(m_intVoteID) ;
            }

            mySurvey.CreateResultImage(Server.MapPath("survey.jpg") ,
                                          MyClass.Util.MyChart.ChartType.Pie ,
                                          300 ,300 , Color.White) ;
            imgSurvey.ImageUrl = "survey.jpg" ;
         }
         catch(Exception e)
         {
#if DEBUG
            Response.Write ("初始化页面错误：" + e.ToString()) ;
            return ;
#endif
            Page.Navigate("error.aspx") ;
         }

      }
}
}

要看这个调查的效果，请到http://210.12.102.95/football 。怎么样，是不是觉得这种编程思路不错呢？什么？还不如直接在aspx文件里面做？不错，如果单做这么一个调查的确直接做要省事的多，但你知不知道，只要有编译好的这个类的dll，不管你怎么改页面，改数据结构，你都可以在15分钟内把你所需要的舆论调查做出来？这就是这两种编程方法最大的区别。希望通过这个例子你能学到一些编程思想把。