使用Repeater的Template

.NET FX提供了一个方法,就是使用Template来在程序运行时对Repeater的显示进行控制.
这里我就不多说了,可以去看MSDN中的相关资料.(嘿嘿,其实我也没搞多少 )..

其实主要是private void lc_DataBinding(object sender, EventArgs e)函数,在DataSource中的数据进行Bind的时候,每Bind一个,都会调用这个函数一次,我们就通过自定义这个函数的实现来完成动态修改格局:)

下面是代码的实现部分:
    /// <summary>
    /// DataControlerType
    /// </summary>
    public enum DataControlerType
    {
        /// <summary>
        /// Repeater
        /// </summary>
        Repeater,
        /// <summary>
        /// DataList
        /// </summary>
        DataList,
        /// <summary>
        /// DataGrid
        /// </summary>
        DataGrid
    }

//     public delegate void DataBinder(object container,Literal lc);

    /// <summary>
    /// DataBinder handler.
    /// </summary>
    public delegate void TemplateDataBinder( object container,Literal lc, string [] columnnames);

    /// <summary>
    /// Summary description for Template.
    /// </summary>
    public class DataTemplateItem : ITemplate
    {
        private ListItemType templateType;
        private string [] columnNames = null ;
        private DataControlerType controlType;
        public TemplateDataBinder mydataBinder = null ;


        /// <summary>
        /// Constructor
        /// </summary>
        /// <param name="columnnames"></param>
        /// <param name="templatetype"></param>
        /// <param name="controltype"></param>
        public DataTemplateItem( string [] columnnames,ListItemType templatetype,DataControlerType controltype)
        {
            templateType = templatetype;
            columnNames = columnnames;
            controlType = controltype;
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="columnnames"></param>
        /// <param name="templatetype"></param>
        /// <param name="controltype"></param>
        /// <param name="dataBinder"></param>
        public DataTemplateItem( string [] columnnames,ListItemType templatetype,DataControlerType controltype,TemplateDataBinder dataBinder)
        {
            mydataBinder = dataBinder;
            templateType = templatetype;
            columnNames = columnnames;
            controlType = controltype;
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="templatetype"></param>
        /// <param name="controltype"></param>
        public DataTemplateItem(ListItemType templatetype,DataControlerType controltype)
        {
            templateType = templatetype;   
            controlType = controltype;
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="templatetype"></param>
        /// <param name="controltype"></param>
        /// <param name="dataBinder"></param>
        public DataTemplateItem(ListItemType templatetype,DataControlerType controltype,TemplateDataBinder dataBinder)
        {
            mydataBinder = dataBinder;
            templateType = templatetype;   
            controlType = controltype;
        }

        public void InstantiateIn(System.Web.UI.Control container)
        {
            Literal lc = new Literal();
            if (mydataBinder == null )
            {
                switch (templateType)
                {
                    case ListItemType.Header:
                        lc.Text = " <TABLE><TR> " ;
                        foreach ( string i in columnNames)
                        {
                            lc.Text += " <TD> " + i + " </TD> " ;
                        }
                        lc.Text += " </TR> " ;
                        break ;
                    case ListItemType.Footer:
                        lc.Text = " </TABLE> " ;
                        break ;
                    case ListItemType.Item:
                    case ListItemType.AlternatingItem:
                        lc.DataBinding += new EventHandler(lc_DataBinding);
                        break ;
                }
            }
            else
            {
                switch (templateType)
                {
                    case ListItemType.Header:
                    case ListItemType.Footer:
                        mydataBinder(container,lc, this .columnNames);
                        break ;
                    case ListItemType.Item:
                    case ListItemType.AlternatingItem:
                        lc.DataBinding += new EventHandler(lc_DataBinding);
                        break ;
                }
            }
            container.Controls.Add(lc);
        }

        private void lc_DataBinding( object sender, EventArgs e)
        {
            Literal lc = (Literal)sender;
            Object container;
            if (controlType == DataControlerType.Repeater)
            {
                container = (RepeaterItem)lc.NamingContainer;
            }
            else if (controlType == DataControlerType.DataList)
            {
                container = (DataListItem)lc.NamingContainer;               
            }
            else // if(controlType == ControlType.DataGrid)
            {
                container = (DataGridItem)lc.NamingContainer;               
            }
           
            if (mydataBinder == null )
            {
                foreach ( string i in columnNames)
                {
                    lc.Text += " <TD> " ;
                    lc.Text += DataBinder.Eval(container, " DataItem. " + i);
                    lc.Text += " </TD> " ;
                }
                lc.Text += " <TR> " ;
            }
            else
            {
                mydataBinder(container,lc,columnNames);
            }
        }
    }

上面的代码中,我定义了一个Delegate TemplateDataBinder ,用来控制显示输出.
使用代码:
            this.Repeater1.DataSource = reader;
            this.Repeater1.HeaderTemplate = new ShowDataTemplate(ListItemType.Header,DataControlerType.Repeater,new ShowDataTemplateDelegate(TempHeader));
            this.Repeater1.FooterTemplate = new ShowDataTemplate(ListItemType.Footer,DataControlerType.Repeater);
            this.Repeater1.ItemTemplate = new ShowDataTemplate(ListItemType.Item,DataControlerType.Repeater,new ShowDataTemplateDelegate(TempItem));
            this.Repeater1.AlternatingItemTemplate = new ShowDataTemplate(ListItemType.AlternatingItem,DataControlerType.Repeater,new ShowDataTemplateDelegate(TempAlternatingItem));
            this.Repeater1.DataBind();


        private void TempHeader (object container,Literal lc,string[] columnNames)
        {
            int index = -1;
            lc.Text += "<table style=/"BORDER-COLLAPSE: collapse/" borderColor=/"#dcdcdc/" cellSpacing=/"0/" cellPadding=/"4/" rules=/"none/" frame=/"box/"><TR>";
            foreach(string i in columnNames)
            {
                index++;
                if(i == "ID"){
                    continue;
                }
                lc.Text += "<TD class=/"frmHeader/" style=/"BORDER-RIGHT: white 2px solid/" background=/"#dcdcdc/">" + columnShows[index] + "</TD>";
            }
            lc.Text += "</TR>";
        }

        private void TempItem (object container,Literal lc,string[] columnNames)
        {
            string id = "";
            lc.Text += "<TR>";
            foreach(string i in columnNames)
            {
                if(i == "ID"){
                    id = (string)DataBinder.Eval(container,"DataItem."+i);;
                    continue;
                }
                lc.Text += "<TD class=/"frmText/">";
                if(i == "Modify")
                {
                    lc.Text += "<a href=Modify.aspx?ID=" + id + ">修改</a>";
                }
                else if(i == "Name" || i == "Title"){
                    lc.Text += "<a href=View.aspx?ID=" + id + ">" + (string)DataBinder.Eval(container,"DataItem."+i) + "</a>";
                }
                else{
                    lc.Text += DataBinder.Eval(container,"DataItem."+i);
                }

                lc.Text += "</TD>";
            }
            lc.Text += "</TR>";
        }