众所周知,ASP.Net中给我们提供了三个数据控件--DataGrid,Repeater,DataList。在这三个控件中,DataGrid控件的功能最强大,Repeater控件最忠实于模版原样,DataList控件则兼而有之。
DataGrid控件太有名了,所以以前用的讲的也很多,Repeater功能太少,没有什么好讲的。这里主要是讲一讲DataList控件。
DataList控件其实功能也很强大,他支持选择、编辑,实现的方法也很简单,不过最令人头疼的就是它不像DataGrid控件一样内置了分页的功能,这么好的一个控件竟然不能分页!!!
确实是一个很让人头疼的事情。
不过,只是DataList没有提供内置的分页功能,但是并不表示,我们不能使用DataList控件来实现分页,既然它不给我分页功能,那只好自己动手了。
下面是全部原代码,其实用到的方法和PHP中的分页差不多,只是这里用的是DataAdapter与DataSet组合,而不是PHP中的SQL语句直接搞定。
<% @ Page Language="C#" %>
<% @ Import Namespace="System.Data" %>
<% @ Import Namespace="System.Data.OleDb" %>
<SCRIPT language=C# Runat="Server">
/*
Create By 飞刀
http://www.aspcn.com
2001-7-25 01:44
Support .Net Framework Beta 2
DataList只有一个数据列,可以有多个按钮列
*/
OleDbConnection MyConn;
int PageSize,RecordCount,PageCount,CurrentPage;
public void Page_Load(Object src,EventArgs e)
{
//设定PageSize
PageSize = 3;
//连接语句
string MyConnString = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source="+Server.MapPath(".")+"..\\images\\db1.mdb;";
MyConn = new OleDbConnection(MyConnString);
MyConn.Open();
//第一次请求执行
if(!Page.IsPostBack)
{
ListBind();
CurrentPage = 0;
ViewState["PageIndex"] = 0;
//计算总共有多少记录
RecordCount = CalculateRecord();
lblRecordCount.Text = RecordCount.ToString();
//计算总共有多少页
PageCount = RecordCount/PageSize;
lblPageCount.Text = PageCount.ToString();
ViewState["PageCount"] = PageCount;
}
}
//计算总共有多少条记录
public int CalculateRecord()
{
int intCount;
string strCount = "select count(*) as co from Score";
OleDbCommand MyComm = new OleDbCommand(strCount,MyConn);
OleDbDataReader dr = MyComm.ExecuteReader();
if(dr.Read())
{
intCount = Int32.Parse(dr["co"].ToString());
}
else
{
intCount = 0;
}
dr.Close();
return intCount;
}
ICollection CreateSource()
{
int StartIndex;
//设定导入的起终地址
StartIndex = CurrentPage*PageSize;
string strSel = "select * from Score";
DataSet ds = new DataSet();
OleDbDataAdapter MyAdapter = new OleDbDataAdapter(strSel,MyConn);
MyAdapter.Fill(ds,StartIndex,PageSize,"Score");
return ds.Tables["Score"].DefaultView;
}
public void ListBind()
{
score.DataSource = CreateSource();
score.DataBind();
lbnNextPage.Enabled = true;
lbnPrevPage.Enabled = true;
if(CurrentPage==(PageCount-1)) lbnNextPage.Enabled = false;
if(CurrentPage==0) lbnPrevPage.Enabled = false;
lblCurrentPage.Text = (CurrentPage+1).ToString();
}
public void Page_OnClick(Object sender,CommandEventArgs e)
{
CurrentPage = (int)ViewState["PageIndex"];
PageCount = (int)ViewState["PageCount"];
string cmd = e.CommandName;
//判断cmd,以判定翻页方向
switch(cmd)
{
case "next":
if(CurrentPage<(PageCount-1)) CurrentPage++;
break;
case "prev":
if(CurrentPage>0) CurrentPage--;
break;
}
ViewState["PageIndex"] = CurrentPage;
ListBind();
}
</SCRIPT>
<FORM id=Form1 runat="server">
共有<asp:Label id=lblRecordCount runat="server" ForeColor="red"></asp:Label>条记录
当前为<asp:Label id=lblCurrentPage runat="server" ForeColor="red"></asp:Label>/<asp:Label id=lblPageCount runat="server" ForeColor="red"></asp:Label>页
<asp:DataList id=score runat="server" EditItemStyle-BackColor="yellow" AlternatingItemStyle-BackColor="Gainsboro" HeaderStyle-BackColor="#aaaadd">
<ITEMTEMPLATE>
<%# DataBinder.Eval(Container.DataItem,"dcid") %><%# DataBinder.Eval(Container.DataItem,"title") %>
<asp:LinkButton id=Linkbutton1 runat="server" CommandName="edit" Text="傻瓜"></asp:LinkButton>
<asp:LinkButton id=btnSelect runat="server" CommandName="edit" Text="编辑"></asp:LinkButton>
</ITEMTEMPLATE>
</asp:DataList>
<asp:LinkButton id=lbnPrevPage runat="server" CommandName="prev" Text="上一页" OnCommand="Page_OnClick"></asp:LinkButton>
<asp:LinkButton id=lbnNextPage runat="server" CommandName="next" Text="下一页" OnCommand="Page_OnClick"></asp:LinkButton>
</FORM>