網(wǎng)站運(yùn)營(yíng)seo文章大全提供全面的站長(zhǎng)運(yùn)營(yíng)經(jīng)驗(yàn)及seo技術(shù)!    一般的web程序員剛剛轉(zhuǎn)到.net或jsp時(shí),往往編程觀念轉(zhuǎn)不過(guò)來(lái),還是按照以前那種結(jié)構(gòu)化的編程思
路來(lái),而不從面向?qū)ο蟮慕嵌瓤紤],造成業(yè)務(wù)邏輯與頁(yè)面html代碼混雜在一起,一旦頁(yè)面原型改變,相應(yīng)
的程序也要修改,這樣造成代碼的可重用性太低。而asp.net或jsp比asp最大的一個(gè)進(jìn)步就是面向?qū)ο螅?br>
使代碼可重用性達(dá)到最高。作為一個(gè)典型的web程序來(lái)說(shuō),一般把它分為三層比較理想,業(yè)務(wù)層,數(shù)據(jù)層
和頁(yè)面顯示層。下面以一個(gè)輿論調(diào)查的例子來(lái)講一下。
    讓我們先來(lái)看一下如果一個(gè)輿論調(diào)查從面向?qū)ο蟮慕嵌葋?lái)考慮應(yīng)該是怎樣的。首先,從數(shù)據(jù)方面來(lái)說(shuō)
,一個(gè)輿論調(diào)查應(yīng)該有一個(gè)調(diào)查主題,然后應(yīng)該有幾個(gè)調(diào)查項(xiàng),最后還應(yīng)該有參加調(diào)查的用戶以及比如調(diào)
查起止時(shí)間等等;其次,從輿論調(diào)查的方法來(lái)說(shuō),很簡(jiǎn)單,一個(gè)投票的方法,然后就是顯示調(diào)查結(jié)果的方
法。知道了上面這些,我們就可以這樣來(lái)構(gòu)造一個(gè)調(diào)查類(lèi):
namespace myclass.util
{
    using system;
    using system.collections ;
    using system.drawing ;
    using myclass.util ;
    /// <summary>
    ///    一個(gè)通用的調(diào)查類(lèi)
    /// </summary>
    public class survey : object
    {
        /// <summary>
        /// 調(diào)查編號(hào)
        /// </summary>
        /// <remarks>
        /// 在數(shù)據(jù)庫(kù)中是varchar型,20字節(jié)
        /// </remakrs>
        protected string m_strid ;
        /// <summary>
        /// 調(diào)查標(biāo)題
        /// </summary>
        protected string m_strtitle ;
        /// <summary>
        /// 調(diào)查開(kāi)始時(shí)間
        /// </summary>
        protected datetime m_datbegintime ;
        /// <summary>
        /// 調(diào)查截止時(shí)間
        /// </summary>
        protected datetime m_datendtime ;
        /// <summary>
        /// 點(diǎn)擊數(shù)
        /// </summary>
        /// <remarks>
        /// 瀏覽人數(shù)
        /// </remarks>
        protected int m_inthits ;
        /// <summary>
        /// 調(diào)查項(xiàng)
        /// </summary>
        protected arraylist m_arritems ;
        //屬性
        /// <summary>
        /// 調(diào)查標(biāo)題
        /// </summary>
        public string title
        {
            get
            {
                return m_strtitle ;
            }
            set
            {
                m_strtitle = value ;
            }
        }
        /// <summary>
        /// 總共點(diǎn)擊數(shù)
        /// </summary>
        public int hits
        {
            get
            {
                return m_inthits ;
            }
            set
            {
                m_inthits = 0 ;
            }
        }
        /// <summary>
        /// 調(diào)查開(kāi)始時(shí)間屬性
        /// </summary>
        public datetime begintime
        {
            get
            {
                return m_datbegintime ;
            }
            set
            {
                m_datbegintime = value ;
            }
        }
        /// <summary>
        /// 調(diào)查截止時(shí)間屬性
        /// </summary>
        public datetime endtime
        {
            get
            {
                return m_datendtime ;
            }
            set
            {
                m_datendtime = value ;
            }
        }
        /// <summary>
        /// 調(diào)查項(xiàng)集合
        /// </summary>
        /// <remarks>是一個(gè)surveyitem類(lèi)的集合</remarks>
        public arraylist items
        {
            get
            {
                return m_arritems ;
            }
            set
            {
                m_arritems = value ;
            }
        }
        
        /// <summary>
        /// 調(diào)查編號(hào)
        /// </summary>
        public string surveyid 
        {
            get
            {
                return m_strid ;
            }
            set
            {
                m_strid = value ;
            }
        }
        /// <summary>
        /// 構(gòu)造函數(shù)
        /// </summary>
        public survey()
        {
            //
            // todo: add constructor logic here
            //
            m_strtitle = "" ;
            m_arritems = new arraylist() ;
        }
        /// <summary>
        /// 重載構(gòu)造函數(shù)
        /// </summary>
        /// <param name="a_strtitle">調(diào)查標(biāo)題 </param>
        /// <remarks>適用于沒(méi)有截止時(shí)間的調(diào)查</remarks>
        public survey(string a_strtitle)
        {
            m_strtitle = a_strtitle ;
            m_datbegintime = datetime.today ;
            m_datendtime = datetime.today ;
            m_arritems = new arraylist() ;
        }
        /// <summary>
        /// 重載構(gòu)造函數(shù)
        /// </summary>
        /// <param name="a_strtitle">調(diào)查標(biāo)題 </param>
        /// <param name="a_datbegintime">開(kāi)始時(shí)間 </param>
        /// <param name="a_datendtime">結(jié)束時(shí)間 </param>
        /// <remarks>適用于有截止時(shí)間的調(diào)查</remarks>
        public survey(string a_strtitle , datetime a_datbegintime , datetime 
a_datendtime)
        {
            m_strtitle = a_strtitle ;
            m_datbegintime = a_datbegintime ;
            m_datendtime = a_datendtime ;
        }
        /// <summary>
        /// 增加調(diào)查項(xiàng)
        /// </summary>
        /// <param name="a_objitem"> </param>
        public void additem(object a_objitem)
        {
            if (a_objitem is surveyitem)
            {
                m_arritems.add(a_objitem) ;
            }
        }
        /// <summary>
        /// 虛函數(shù)
        /// </summary>
        /// <param name="a_intid">該項(xiàng)編號(hào) </param>
        public virtual void vote(int a_intid) 
        {
            
        }
        /// <summary>
        /// 虛函數(shù),保存到數(shù)據(jù)庫(kù)
        /// </summary>
        /// <param name="a_objitem"> </param>
        public virtual void saveitem(object a_objitem)
        {
            
        }
        /// <summary>
        /// 虛函數(shù),保存調(diào)查到數(shù)據(jù)庫(kù)
        /// </summary>
        public virtual void savetodatabase(string m_strsurveyid)
        {
            throw(new exception("基類(lèi)函數(shù)不能直接使用")) ;
        }
        /// <summary>
        ///  從數(shù)據(jù)庫(kù)中取得調(diào)查及調(diào)查項(xiàng)
        /// </summary>
        /// <param name="a_intid">對(duì)應(yīng)數(shù)據(jù)庫(kù)中的id </param>
        public virtual void loadfromdatabase(string a_strid)
        {
            
        }
        /// <summary>
        /// 查找調(diào)查項(xiàng)
        /// </summary>
        /// <param name="a_intid">調(diào)查項(xiàng)編號(hào) </param>
        public surveyitem getitem(int a_intid)
        {
            if (a_intid > 0 && a_intid < m_arritems.count)
            {
                return (surveyitem)(m_arritems[a_intid]) ;
            }
            else
            {
                throw(new exception("調(diào)查項(xiàng)下標(biāo)越界")) ;
            }
        }
        
        /// <summary>
        /// 查找調(diào)查項(xiàng)
        /// </summary>
        /// <param name="a_strtext">調(diào)查項(xiàng)標(biāo)題 </param>
        /// <remarks>根據(jù)標(biāo)題查找調(diào)查項(xiàng),找到就返回它的序號(hào),否則就返回-1</remarks>
        public int indexof(string a_strtext)
        {
            for (int i = 0 ; i < m_arritems.count ; i ++)
            {
                if (a_strtext == ((surveyitem)m_arritems[i]).text)
                {
                    return i ;
                }
            }
            return -1 ;
        }
        /// <summary>
        /// 查找調(diào)查項(xiàng)
        /// </summary>
        /// <param name="a_intid">調(diào)查項(xiàng)編號(hào) </param>
        /// <remarks>
        ///  根據(jù)調(diào)查項(xiàng)標(biāo)號(hào)來(lái)查找調(diào)查項(xiàng),如果找到返回序號(hào),否則返回-1</remarks>
        public int indexof(int a_intid)
        {
            for ( int i = 0 ; i < m_arritems.count ; i ++)
            {
                if (a_intid == ((surveyitem)m_arritems[i]).id)
                {
                    return i ;
                }
            }
            return - 1 ;
        }
        /// <summary>
        /// 顯示結(jié)果
        /// </summary>
        /// <param name="a_strfilename">生成圖片的保存位置 </param>
        public void createresultimage(string a_strfilename , mychart.charttype 
a_intcharttype , 
                                int a_intwidth , int 
a_intheight , color a_objbackcolor)
        {
            //定義一個(gè)顏色數(shù)組
            arraylist itemcolors = new arraylist() ;
            itemcolors.add(color.red) ;
            itemcolors.add(color.black) ;
            itemcolors.add(color.blue) ;
            itemcolors.add(color.deepskyblue) ;
            itemcolors.add(color.firebrick) ;
            itemcolors.add(color.orange) ;
            itemcolors.add(color.green) ;
            itemcolors.add(color.whitesmoke) ;
            itemcolors.add(color.tan) ;
            itemcolors.add(color.darkseagreen) ;
            itemcolors.add(color.fuchsia) ;
            itemcolors.add(color.goldenrod) ;
            mychart mychart = new mychart(m_strtitle , a_objbackcolor , 
a_intwidth , 
                                a_intheight , a_intcharttype 
, "人次") ;
            for (int i = 0 ; i < m_arritems.count ; i++)
            {
                //調(diào)查項(xiàng)
                surveyitem item = (surveyitem)m_arritems[i] ;
                //圖表項(xiàng)
                mychart.additem(new chartitem(item.text , item.count , 
(color)itemcolors[i])) ;
 
            }
            try
            {
                mychart.create(a_strfilename) ;
            }
            catch(exception e)
            {
                throw(new exception(e.tostring())) ;
            }
        }
        
    }
    /// <summary>
    /// 調(diào)查項(xiàng)類(lèi)
    /// </summary>
    public class surveyitem : object
    {
        /// <summary>
        /// 調(diào)查項(xiàng)編號(hào),對(duì)應(yīng)將來(lái)數(shù)據(jù)庫(kù)中的id
        /// </summary>
        protected int m_intid ;
        /// <summary>
        /// 調(diào)查項(xiàng)標(biāo)題
        /// </summary>
        protected string m_strtext ;
        /// <summary>
        /// 調(diào)查項(xiàng)描述
        /// </summary>
        protected string m_strdescription ;
        /// <summary>
        /// 調(diào)查項(xiàng)數(shù)量
        /// </summary>
        protected int m_intcount ;
        public int id
        {
            get
            {
                return m_intid ;
            }
            set
            {
                m_intid = value ;
            }
        }
        /// <summary>
        /// 構(gòu)造函數(shù)
        /// </summary>
        public surveyitem()
        {
            m_strtext = "" ;
            m_strdescription = "" ;
            m_intcount = 0 ;
        }
        //屬性
        /// <summary>
        /// 調(diào)查項(xiàng)標(biāo)題屬性
        /// </summary>
        public string text
        {
            get
            {
                return m_strtext ;
            }
            set
            {
                m_strtext = value ;
            }
        }
        /// <summary>
        /// 調(diào)查項(xiàng)描述屬性
        /// </summary>
        public string description
        {
            get
            {
                return m_strdescription ;
            }
            set
            {
                m_strdescription = value ;
            }
        }
        /// <summary>
        /// 調(diào)查項(xiàng)數(shù)量屬性
        /// </summary>
        public int count
        {
            get
            {
                return m_intcount ;
            }
            set
            {
                m_intcount = value ;
            }
        }
        //函數(shù)
        /// <summary>
        /// 重載構(gòu)造函數(shù)
        /// </summary>
        /// <param name="a_intid">調(diào)查項(xiàng)編號(hào) </param>
        /// <param name="a_strtext">調(diào)查項(xiàng)標(biāo)題 </param>
        /// <param name="a_strdescription">調(diào)查項(xiàng)描述 </param>
        /// <param name="a_intcount">調(diào)查項(xiàng)數(shù)量 </param>
        public surveyitem(int a_intid , string a_strtext , 
                        string a_strdescription , int a_intcount)
        {
            m_intid = a_intid ;
            m_strtext = a_strtext ;
            m_strdescription = a_strdescription ;
            m_intcount = a_intcount ;
        }
        public surveyitem(string a_strtext)
        {
            m_strtext = a_strtext ;
        }
    }
}
一個(gè)基本的調(diào)查類(lèi)就做好了,這個(gè)可以作為業(yè)務(wù)層。但是你可以發(fā)現(xiàn)實(shí)際上這個(gè)類(lèi)現(xiàn)在什么都做不了,原
因很簡(jiǎn)單,因?yàn)闆](méi)有同數(shù)據(jù)庫(kù)掛接。眾所周知,沒(méi)有數(shù)據(jù)庫(kù)的支持什么都是白搭,那么,我們現(xiàn)在如何來(lái)
掛接數(shù)據(jù)庫(kù),也就是做數(shù)據(jù)層呢?