目录

关于数据感应

BaseDataList 类

范例运行环境

pageview 方法

设计

实现

调用示例

数据源

调用

小结

关于数据感应

数据感应也即数据捆绑，是一种动态的，Web控件与数据源之间的交互，本文将继续介绍以与数据库提取数据并捆绑控件为例，讲解 C# 创建适用于 BaseDataList 类(如DataGrid)的通用分页数据显示方法。

BaseDataList 类

BaseDataList 类是包括如 DataList 、DataGrid 服务器控件的基类，本文我们以 DataGrid 服务器控件控件，并结合 MS SQL SERVER 和 达梦数据库，以数据分页的形式，绑定 DataGrid进行显示。

更多 BaseDataList 类的介绍请参照如下链接：

https://learn.microsoft.com/ZH-CN/dotnet/api/system.web.ui.webcontrols.basedatalist?view=netframework-4.8.1&viewFallbackFrom=net-7.0

范例运行环境

操作系统： Windows Server 2019 DataCenter

.net版本： .netFramework4.7.1 或以上

开发工具：VS2019  C#

数据提取：在这里我们以能够支持 MS SQL Server 2016、国产达梦数据 8 的通用数据库内容提取方法为例， 生成数据源需要利用 ADO.NET 中的数据提供者对象包括IDbConnection、IDbCommand、IDbDataParameter等，如何使用这些对象请参考我的文章：

《C#实现 IDbConnection / IDbCommand 等相关通用数据接口》

pageview 方法

设计

pageview 方法内置了分页函数写法（目前支持 MS SQL Server 2016 和国产达梦 8 数据库 ），另外传递SQL关键命令及配置相关参数，将数据源分页感应到指定的 BaseDataList 类控件上，其参数说明如下表：

实现

pageview 方法完整代码如下：

public string pageview(string DbServerType,string strConn,string[] webctls,string navsender,System.Web.UI.WebControls.BaseDataList dbgrid,string DisplayFieldList,string SelectedFieldList,string OrderFieldList,string FromTableList,string WhereStatements,ArrayList paras,string keyfield,string OuterFromTableList,string OuterWhereStatements,bool movWhereToOuter,ArrayList GroupFuncs){string[] defaultobj=new string[5];defaultobj[0]="q_pageno"; //当前页defaultobj[1]="q_pagecount"; //页总数defaultobj[2]="q_recordcount"; //总记录数defaultobj[3]="q_pagesize"; //可选择的每页记录数defaultobj[4]="q_pageno_label"; //可选择的每页记录数if(webctls==null){webctls=defaultobj;}if(webctls.GetLength(0)<4){webctls=defaultobj;}ObjectEx oe=new ObjectEx();oe.RunAt=RunAt;oe.FindContainer=FindContainer;int _npc=0;int _now=1;try{_now=int.Parse(oe.GetBaseClassText(webctls[0]));if(oe.GetBaseClassText(webctls[1])!=""){_npc=int.Parse(oe.GetBaseClassText(webctls[1]));} }catch(Exception){_now=1;_npc=1;oe.SetBaseClassText(webctls[0],"1");oe.SetBaseClassText(webctls[1],"1");}string navtype=oe.GetBaseClassArg(navsender);if(navtype=="nav1"){_now=1;}if(navtype=="nav2"){_now--;}if(navtype=="nav3"){_now++;}if(navtype=="nav4"){_now=_npc;}if(navtype=="nav5"){_now=int.Parse(oe.GetBaseClassText(webctls[0]));}if(_now>_npc){_now=_npc;}if(_now<1){_now=1;}_now--; IDbConnection Conn = GetConnection(DbServerType, strConn); IDataReader myDr;string _countf=keyfield;string _pagesize=oe.GetBaseClassList(webctls[3],"Value");_pagesize=(_pagesize==""?"50":_pagesize);if(movWhereToOuter==true){ WhereStatements=WhereStatements.Replace("where 1=1","");if(OuterWhereStatements.IndexOf("{0}")==-1){OuterWhereStatements+=" "+WhereStatements;}else{OuterWhereStatements=string.Format(OuterWhereStatements,WhereStatements);}WhereStatements="";} string groupf="",resultf="",declare="",intolist= "RecordCount";if(GroupFuncs!=null){for(int i=0;i<GroupFuncs.Count;i++){string[] rv=(string[])GroupFuncs[i]; if (DbServerType.ToLower() == "dm8") { intolist += "," + rv[1] ; groupf += "," + rv[0]; resultf += "," + rv[1] + " " + rv[1]; declare += " " + rv[1] + " " + rv[2] + " "; } else { groupf += ",@" + rv[1] + "=" + rv[0]; resultf += ",@" + rv[1] + " " + rv[1]; declare += " declare @" + rv[1] + " " + rv[2] + " "; } }}string CommandText = "DECLARE @PageIndex INT "+" DECLARE @PageSize INT "+" DECLARE @RecordCount INT "+" DECLARE @PageCount INT "+declare+"SET @PageIndex="+_now.ToString()+" "+"SET @PageSize="+_pagesize+" "+"SELECT @RecordCount =COUNT("+_countf+")"+groupf+" FROM "+FromTableList+" "+WhereStatements+" "+"SET @PageCount = CEILING(@RecordCount * 1.0 / @PageSize) "+" select @recordcount rc,@pagecount pc"+resultf+" SELECT "+DisplayFieldList+" FROM "+"(SELECT "+SelectedFieldList+","+"ROW_NUMBER() OVER (ORDER BY "+OrderFieldList+") AS sn "+"FROM "+FromTableList+" "+WhereStatements+") AS T "+OuterFromTableList+" WHERE T.sn > (@PageIndex * @PageSize) and T.sn <= ((@PageIndex+1) * @PageSize) "+OuterWhereStatements; if (DbServerType.ToLower() == "dm8") { CommandText = "declare PageIndex INT; " + " PageSize INT; " + " RecordCount INT; " + " PageCount INT; " + declare + "begin SET PageIndex=" + _now.ToString() + "; " + "SET PageSize=" + _pagesize + "; " + "SELECT COUNT(" + _countf + ") " + groupf +" into "+intolist+ " FROM " + FromTableList + " " + WhereStatements + " ;" + "SET PageCount = CEILING(RecordCount * 1.0 / PageSize) ;" + " select recordcount rc,pagecount pc" + resultf +";"+ " SELECT " + DisplayFieldList + " FROM " + "(SELECT " + SelectedFieldList + "," + "ROW_NUMBER() OVER (ORDER BY " + OrderFieldList + ") AS sn " + "FROM " + FromTableList + " " + WhereStatements + ") AS T " + OuterFromTableList + " WHERE T.sn > (PageIndex * PageSize) and T.sn <= ((PageIndex+1) * PageSize) " + OuterWhereStatements+" ;"+ " end;"; }string _info="";try{ ArrayList _paras = new ArrayList();if(paras!=null){for(int i=0;i<paras.Count;i++){ if (DbServerType.ToLower() == "dm8") { _paras.Add(paras[i] as DmParameter); } else { _paras.Add((SqlParameter)paras[i]); }}} IDbCommand Cmd = GetCommand(DbServerType, CommandText, _paras, Conn);Conn.Open(); if (DbServerType.ToLower() == "dm8") { myDr = Cmd.ExecuteReader() as DmDataReader; } else { myDr = Cmd.ExecuteReader() as SqlDataReader; } if (myDr.Read()){ int pc=int.Parse(myDr["pc"].ToString());int rc=int.Parse(myDr["rc"].ToString());oe.SetBaseClassText(webctls[1],pc.ToString());oe.SetBaseClassText(webctls[2],rc.ToString());oe.SetBaseClassText(webctls[0],(_now+1).ToString());if(webctls.Length>4){oe.SetBaseClassText(webctls[4],(_now+1).ToString());}if(GroupFuncs!=null){for(int i=0;i<GroupFuncs.Count;i++){string[] rv=(string[])GroupFuncs[i];oe.SetBaseClassText(rv[3],myDr[rv[1]].ToString());}}}if(myDr.NextResult()){dbgrid.DataSource=myDr;dbgrid.DataBind();}myDr.Close();}catch (Exception ex){_info=ex.Message;}finally{Conn.Close();Conn.Dispose();}return _info;}//pageview

pageview方法中涉及对控件ID在Page页面的查找 ，及对基类的一些属性如Text进行设置，因此设计了一个 ObjectEx 类，实现一些控件的查找和设置方法，该类设计如下：

类代码如下：

public class ObjectEx{public System.Web.UI.HtmlControls.HtmlForm RunAt=null;public System.Web.UI.Control FindContainer=null;public string GetBaseClassArg(string webctl){System.Web.UI.Control btnctl;btnctl=RunAt.FindControl(webctl);if(FindContainer!=null){btnctl=FindContainer.FindControl(webctl);}if(btnctl==null){return "";}if(btnctl.GetType()==typeof(System.Web.UI.HtmlControls.HtmlInputButton)){if(((System.Web.UI.HtmlControls.HtmlInputButton)btnctl).Attributes["CommandArgument"]!=null)return ((System.Web.UI.HtmlControls.HtmlInputButton)btnctl).Attributes["CommandArgument"].ToString();}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.Button)){return ((System.Web.UI.WebControls.Button)btnctl).CommandArgument;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.ImageButton)){return ((System.Web.UI.WebControls.ImageButton)btnctl).CommandArgument;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.LinkButton)){return ((System.Web.UI.WebControls.LinkButton)btnctl).CommandArgument;}return "";}public string GetBaseClassText(string webctl){System.Web.UI.Control btnctl;btnctl=RunAt.FindControl(webctl);if(FindContainer!=null){btnctl=FindContainer.FindControl(webctl);}if(btnctl==null){return "";}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.TextBox)){return ((System.Web.UI.WebControls.TextBox)btnctl).Text;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.Label)){return ((System.Web.UI.WebControls.Label)btnctl).Text;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.Button)){return ((System.Web.UI.WebControls.Button)btnctl).Text;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.LinkButton)){return ((System.Web.UI.WebControls.LinkButton)btnctl).Text;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.HyperLink)){return ((System.Web.UI.WebControls.HyperLink)btnctl).Text;}return "";}public void SetBaseClassText(string webctl,string values){System.Web.UI.Control btnctl;btnctl=RunAt.FindControl(webctl);if(FindContainer!=null){btnctl=FindContainer.FindControl(webctl);}if(btnctl==null){return;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.TextBox)){((System.Web.UI.WebControls.TextBox)btnctl).Text=values;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.Label)){((System.Web.UI.WebControls.Label)btnctl).Text=values;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.Button)){((System.Web.UI.WebControls.Button)btnctl).Text=values;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.LinkButton)){((System.Web.UI.WebControls.LinkButton)btnctl).Text=values;}if(btnctl.GetType()==typeof(System.Web.UI.WebControls.HyperLink)){((System.Web.UI.WebControls.HyperLink)btnctl).Text=values;}}public string GetBaseClassList(string webctl,string gettype){System.Web.UI.Control btnctl;btnctl=RunAt.FindControl(webctl);if(FindContainer!=null){btnctl=FindContainer.FindControl(webctl);}if(btnctl==null){return "";}return (gettype.ToLower()=="text"?((System.Web.UI.WebControls.ListControl)btnctl).SelectedItem.Text:((System.Web.UI.WebControls.ListControl)btnctl).SelectedItem.Value);}}//ObjectEx Class

调用示例

数据源

我们以 MS SQL SERVER 为例，提取信息发布系统列表信息，如下图数据显示：

表（wp_infos）设计基本情况如下表：

调用

在页面放置一个ID为 dbgrid 的 DataGrid 控件和一系列的导航按钮等控件，前端示例代码如下： 

<div align="center" id="panel"><table border="0" cellpadding="0" cellspacing="0" width="100%" style="border:1px solid #CFE2FF; border-top:2px solid #1A5FC9; background-color:#F7F9FF;" id="table310"><tr> <td align="center"><asp:DataGrid ID=dbgrid ShowHeader="True"ShowFooter="False" CellPadding="0" Border="0" forecolor="black" Runat=server EnableViewState=True /> </td></tr><tr> <td align="right"><table border="0" width="100%" cellspacing="0" cellpadding="0" id="table314" bgcolor="#EEF4FF"><tr><td align="right" valign="middle" style="display:none;"> <asp:ImageButton ID=ntop CommandArgument=nav1 OnClick=navpage ImageUrl="images/nav1.jpg" Visible="false" Runat=server/>&nbsp;&nbsp;&nbsp;&nbsp;<asp:ImageButton ID=nbtm CommandArgument=nav4 OnClick=navpage ImageUrl="images/nav4.jpg" Visible="false" Runat=server/><asp:dropdownlist id="x_pagesize" runat="server" style="font-size:9pt;font-family:宋体" Visible="false"> <asp:ListItem Text="10" Value="10" /><asp:ListItem Text="20" Value="20" selected="true"/><asp:ListItem Text="30" Value="30" /><asp:ListItem Text="40" Value="40" /><asp:ListItem Text="50" Value="50" /><asp:ListItem Text="100" Value="100" /></asp:dropdownlist><asp:ImageButton Text="go" id="gotopage" Visible="false" OnClick=navpage CommandArgument=nav5 ImageUrl="images/nav5.jpg" Runat=server/></td><td width="515" height="30"></td><td valign="middle" width="100" align="right">共计<asp:Label ID=nrc Runat=server/>条记录</td><td valign="middle" width="4"><img src="../images/2012/inner/inner_dg_l.jpg"></td><td valign="middle" width="46" align="center"><asp:Label ID=ngo Text="1" Runat=server/>/<asp:Label ID=npc Runat=server/></td><td valign="middle" align="left" width="135"><asp:ImageButton ID=nprv CommandArgument=nav2 OnClick=navpage ImageUrl="../images/2012/inner/inner_dg_btn_p.jpg" Runat=server/>&nbsp;&nbsp;<asp:ImageButton ID=nnxt CommandArgument=nav3 OnClick=navpage ImageUrl="../images/2012/inner/inner_dg_btn_n.jpg" Runat=server/></td> </tr></table> </td> </tr> </table></div>

后端调用示例代码如下：

void navpage(Object sender,EventArgs e){ string _sql=" title,pub_time"; string _wherecon=""; String arg =""; try{ arg=((ImageButton)sender).CommandArgument; }catch(Exception xe){ arg=((LinkButton)sender).CommandArgument; } string DisplayFieldList="sn 序号,title 标题名称,pub_time 发布时间"; string SelectedFieldList=_sql; string OrderFieldList="pub_time desc"; string FromTableList="wp_infos"; string WhereStatements=""; object[] rv=GetWhere(); WhereStatements=rv[0].ToString(); string[] webctls=new string[4]; webctls[0]="ngo"; webctls[1]="npc"; webctls[2]="nrc"; webctls[3]="x_pagesize"; pageview("sqlserver","您的数据连接串",webctls,((Control)sender).ID,dbgrid,DisplayFieldList,SelectedFieldList,OrderFieldList,FromTableList,WhereStatements,(ArrayList)rv[1],"id");}object[] GetWhere(){ object[] rv=new object[2]; string WhereStatements=" where 1=1 "; ArrayList paras = new ArrayList(); if(q_title.Text!=""){ SqlParameter para2=new SqlParameter("@title",SqlDbType.NVarChar,200); para2.Value=q_title.Text; paras.Add(para2); WhereStatements+=" and title like @title "; } if(q_pub_time1.Text!=""){ SqlParameter para4=new SqlParameter("@pub_time1",SqlDbType.DateTime); para4.Value=q_pub_time1.Text; paras.Add(para4); WhereStatements+=" and pub_time>=@pub_time1 "; } if(q_pub_time2.Text!=""){ SqlParameter para5=new SqlParameter("@pub_time2",SqlDbType.DateTime); para5.Value=q_pub_time2.Text; paras.Add(para5); WhereStatements+=" and pub_time<=@pub_time2 "; } rv[0]=WhereStatements; rv[1]=paras; return rv; }

小结

本方法同时适用于达梦8数据库的数据分页技术，我们可以根据自己的实际需要扩充兼容的数据库功能，范例中所需数据库驱动链接库，请下载我的资源：

https://download.csdn.net/download/michaelline/89235824

感谢您的阅读，希望本文能够对您有所帮助。