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DataGrid自定义分页以及几种常用的删除方法

Posted on 2005-09-28 10:17  一个人的天空  阅读(1629)  评论(0编辑  收藏  举报

此例子使用的是NorthWind数据库,里面用了分页存储过程,具体实现根据你设置的 DataGrid的每页的大小,每次从数据库中取出相对的记录,具体效果如图。
下面还把常用的几种删除记录的方式也写了一下(1.根据选中的CheckBox,一次删除多条记录,2.属性生成器里添加的删除按钮列删除,3.在模板列中放入Button按钮,每次删除之前都会有提示框,代码如下)
说明:由于这个程序我用到了数据访问层,所以数据库访问层的代码没有放上来,自己可以写一下,用到地方下面的代码会有说明
关于删除的方法,由于NorthWind表是SQLSERVER自带的,所以用了一个方法代替一下,并没有真正的删除记录,代码我注释掉了,不过逻辑是一样的。                       
关于页面的跳转,我用了DropDownList控件和TextBox控件,用DropDownList控件看的清楚,使用方便,但是一旦记录很多,页数增加,那就要每次都清除,每次加载一次,可能会影响效率,所以我用了两种方法,供其选择。                   
希望这个例子对大家有所帮助,也希望能够多提意见!

以下为存储过程,一个是分页存储过程,一个是得到总记录的存储过程
分页存储过程:
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO


ALTER   PROCEDURE Test_GetOrders
(@PAGESIZE INT,  --页面大小,如每页存储20条记录
@PAGEINDEX INT   --当前页码
)
AS
SET NOCOUNT ON
BEGIN

DECLARE @INDEXTABLE TABLE(ID INT IDENTITY(1,1),NID INT)  --定义表变量

DECLARE @PAGELOWERBOUND INT  --定义此页的底码

DECLARE @PAGEUPPERBOUND INT  --定义此页的顶码

SET @PAGELOWERBOUND=(@PAGEINDEX-1)*@PAGESIZE

SET @PAGEUPPERBOUND=@PAGELOWERBOUND+@PAGESIZE

SET ROWCOUNT @PAGEUPPERBOUND

INSERT INTO @INDEXTABLE(NID) SELECT OrderID FROM Orders ORDER BY OrderID DESC

SELECT ORDERID,CUSTOMERID,CONVERT(CHAR(10),ORDERDATE,120) AS ORDERDATE,
SHIPCITY,SHIPCOUNTRY,ISNULL(SHIPREGION,'无') AS SHIPREGION
FROM ORDERS A
INNER JOIN @INDEXTABLE T
ON A.ORDERID=T.NID
WHERE T.ID>@PAGELOWERBOUND AND T.ID<=@PAGEUPPERBOUND
ORDER BY T.ID

END

SET NOCOUNT OFF


GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO

得到总记录的存储过程:
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO

ALTER  PROC GetOrderCount
AS
--得到ORDERS表的总记录数
SELECT COUNT(*) FROM ORDERS

GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO

前台的代码:

<%@ Page language="c#" Codebehind="OrdersPage.aspx.cs" AutoEventWireup="false" Inherits="NetTest.OrdersPage" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
 <HEAD>
  <title>NorthWind数据库Orders表的分页例子</title>
  <meta name="GENERATOR" Content="Microsoft Visual Studio .NET 7.1">
  <meta name="CODE_LANGUAGE" Content="C#">
  <meta name="vs_defaultClientScript" content="JavaScript">
  <link href="Css/BasicLayout.css" rel="stylesheet" type="text/css">
  <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">
 </HEAD>
 <body MS_POSITIONING="GridLayout">
  <script language="javascript">
   function SelectAll()
   {
    var len=document.Form1.elements.length;
    var i;
    for (i=0;i<len;i++)
    {
     if (document.Form1.elements[i].type=="checkbox")
     {
      document.Form1.elements[i].checked=true;        
     }
    }
   }
   function UnSelectAll()
   {
    var len=document.Form1.elements.length;
    var i;
    for (i=0;i<len;i++)
    {
     if (document.Form1.elements[i].type=="checkbox")
     {
      document.Form1.elements[i].checked=false;        
     }
    }
   }
  </script>
  <form id="Form1" method="post" runat="server">
   <table align="center" border="0" width="60%">
    <tr>
     <td align="right">
      <asp:RegularExpressionValidator id="RegularExpressionValidator1" runat="server" ErrorMessage="页数只能为数字" Display="None"
       ControlToValidate="txtPage" ValidationExpression="\d{0,10}"></asp:RegularExpressionValidator>
      <asp:ValidationSummary id="ValidationSummary1" runat="server" ShowMessageBox="True" ShowSummary="False"></asp:ValidationSummary></td>
    </tr>
    <TR>
     <TD align="center"><font style="FONT-SIZE: 10pt">共</font>
      <asp:label id="lbTotalPage" runat="server" CssClass="pageLinks"></asp:label>
      <font style="FONT-SIZE: 10pt">页/共
       <asp:label id="lbTotalCount" runat="server" CssClass="pageLinks"></asp:label>
       记录&nbsp; 当前</font>
      <asp:label id="lbCurrentPage" runat="server" CssClass="pageLinks"></asp:label>
      <font style="FONT-SIZE: 10pt">页</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
      <font style="FONT-SIZE: 10pt">跳转到</font>
      <asp:dropdownlist id="ddlPage" runat="server" AutoPostBack="True" Width="65px"></asp:dropdownlist>
      <font style="FONT-SIZE: 10pt">页</font>
      <asp:TextBox id="txtPage" runat="server" Width="43px"></asp:TextBox>
      <asp:Button id="btnGo" runat="server" CssClass="redButtonCss" Width="34px" Text="GO"></asp:Button><FONT size="2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
      </FONT>
     </TD>
    </TR>
    <tr>
     <td align="right"><INPUT type="button" value="全部选择" onclick="SelectAll()"><FONT face="宋体">&nbsp;&nbsp;
      </FONT><INPUT type="button" value="全部取消" onclick="UnSelectAll()"><FONT face="宋体">&nbsp;&nbsp;
      </FONT>
      <asp:Button id="btnDelete" runat="server" Text="删除"></asp:Button><FONT face="宋体">&nbsp;&nbsp;&nbsp;
      </FONT>
     </td>
    </tr>
    <tr>
     <td>
      <asp:DataGrid id="dbOrders" runat="server" AutoGenerateColumns="False" Width="100%" BorderStyle="None"
       BorderColor="#93BEE2" PageSize="20" AllowCustomPaging="True" AllowPaging="True" DataKeyField="OrderID">
       <ItemStyle Font-Size="X-Small" HorizontalAlign="Center" Height="25px" BackColor="#CCFFFF"></ItemStyle>
       <HeaderStyle Font-Size="X-Small" Font-Bold="True" HorizontalAlign="Center" Height="25px" BackColor="#6699FF"></HeaderStyle>
       <Columns>
        <asp:TemplateColumn>
         <ItemTemplate>
          <FONT face="宋体">
           <asp:CheckBox id="cbFlag" runat="server"></asp:CheckBox></FONT>
         </ItemTemplate>
        </asp:TemplateColumn>
        <asp:BoundColumn DataField="OrderID" HeaderText="订单编号"></asp:BoundColumn>
        <asp:BoundColumn DataField="CustomerID" HeaderText="客户编号"></asp:BoundColumn>
        <asp:BoundColumn DataField="OrderDate" HeaderText="订单日期"></asp:BoundColumn>
        <asp:BoundColumn DataField="ShipCity" HeaderText="运输城市"></asp:BoundColumn>
        <asp:BoundColumn DataField="ShipCountry" HeaderText="运输国家"></asp:BoundColumn>
        <asp:BoundColumn DataField="ShipRegion" HeaderText="运输区域"></asp:BoundColumn>
        <asp:ButtonColumn Text="删除" CommandName="Delete"></asp:ButtonColumn>
        <asp:TemplateColumn>
         <ItemTemplate>
          <FONT face="宋体">
           <asp:Button id="btnADelete" runat="server" CssClass="redButtonCss" CommandName="Delete" Text="删除"></asp:Button></FONT>
         </ItemTemplate>
        </asp:TemplateColumn>
       </Columns>
       <PagerStyle Visible="False"></PagerStyle>
      </asp:DataGrid>
     </td>
    </tr>
    <tr>
     <TD align="center" height="30"><B><asp:linkbutton id="FirstPage" runat="server" CssClass="pageLinks" Text="[First Page]" CommandName="First"
        OnCommand="NavigationLink_Click">第一页</asp:linkbutton>&nbsp;&nbsp;&nbsp;
       <asp:linkbutton id="PreviousPage" runat="server" CssClass="pageLinks" Text="[Previous Page]" CommandName="Prev"
        OnCommand="NavigationLink_Click">上一页</asp:linkbutton>&nbsp;&nbsp;&nbsp;
       <asp:linkbutton id="NextPage" runat="server" CssClass="pageLinks" Text="[Next Page]" CommandName="Next"
        OnCommand="NavigationLink_Click">下一页</asp:linkbutton>&nbsp;&nbsp;&nbsp;
       <asp:linkbutton id="LastPage" runat="server" CssClass="pageLinks" Text="[Last Page]" CommandName="Last"
        OnCommand="NavigationLink_Click">末一页</asp:linkbutton></B>
     </TD>
    </tr>
   </table>
  </form>
 </body>
</HTML>

后台代码:

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;
using DataBaseClass;
using System.Data.SqlClient;
namespace NetTest
{
 /// <summary>
 /// OrdersPage 的摘要说明。
 /// </summary>
 public class OrdersPage : System.Web.UI.Page
 {
  protected System.Web.UI.WebControls.Label lbTotalPage;
  protected System.Web.UI.WebControls.Label lbTotalCount;
  protected System.Web.UI.WebControls.Label lbCurrentPage;
  protected System.Web.UI.WebControls.DropDownList ddlPage;
  protected System.Web.UI.WebControls.LinkButton FirstPage;
  protected System.Web.UI.WebControls.LinkButton PreviousPage;
  protected System.Web.UI.WebControls.LinkButton NextPage;
  protected System.Web.UI.WebControls.DataGrid dbOrders;
  protected System.Web.UI.WebControls.LinkButton LastPage;
  private ClassDataGrid CDG=new ClassDataGrid();//数据访问层的类,定义的的一个实例
  protected System.Web.UI.WebControls.Button btnGo;
  protected System.Web.UI.WebControls.TextBox txtPage;
  protected System.Web.UI.WebControls.ValidationSummary ValidationSummary1;
  protected System.Web.UI.WebControls.RegularExpressionValidator RegularExpressionValidator1;
  protected System.Web.UI.WebControls.Button btnDelete;
  protected Int32 CurrentPageNumber = 1;//初始化,设置当前页为1,随时都要使用
  private void Page_Load(object sender, System.EventArgs e)
  {
   if(!IsPostBack)
   {
    BindData();
    btnDelete.Attributes ["onclick"]="javascript:return confirm('您确认要删除吗?');";
   }
  }

  #region Web 窗体设计器生成的代码
  override protected void OnInit(EventArgs e)
  {
   //
   // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
   //
   InitializeComponent();
   base.OnInit(e);
  }
  
  /// <summary>
  /// 设计器支持所需的方法 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// </summary>
  private void InitializeComponent()
  {   
   this.ddlPage.SelectedIndexChanged += new System.EventHandler(this.ddlPage_SelectedIndexChanged);
   this.btnGo.Click += new System.EventHandler(this.btnGo_Click);
   this.dbOrders.ItemCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.dbOrders_ItemCommand);
   this.dbOrders.DeleteCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.dbOrders_DeleteCommand);
   this.dbOrders.ItemDataBound += new System.Web.UI.WebControls.DataGridItemEventHandler(this.dbOrders_ItemDataBound);
   this.btnDelete.Click += new System.EventHandler(this.btnDelete_Click);
   this.Load += new System.EventHandler(this.Page_Load);

  }
  #endregion

  public Int32 GetCountOrders()
  {
   Int32 Tcount=Int32.Parse(CDG.GetOrderCount());//此处用到了数据访问层,得到总记录数,代码要自己写一下
   return Tcount;
  }

  protected void NavigationLink_Click ( Object sender, CommandEventArgs e )//此事件为HTML代码里注册(事件为OnCommand)
  {
   switch ( e.CommandName )//根据设置的CommandName属性判断
   {
    case "First":
     CurrentPageNumber = 1;
     break;
    case "Last":
     CurrentPageNumber = Int32.Parse ( lbTotalPage.Text );
     break;
    case "Next":
     CurrentPageNumber = Int32.Parse ( lbCurrentPage.Text ) + 1;
     break;
    case "Prev":
     CurrentPageNumber = Int32.Parse ( lbCurrentPage.Text ) - 1;
     break;
   }
   BindData();
   
  }

  public void BindData()
  {
   lbCurrentPage.Text = CurrentPageNumber.ToString();
   int PageSize=int.Parse(dbOrders.PageSize.ToString());
   
   //绑定DATAGRID,此处用到数据访问层,只要可以绑定就可以了(DataSet,DataTable都可以),这里的代码要自己写一下
   SqlDataReader dr=CDG.GetOrders(PageSize,CurrentPageNumber);
   dbOrders.DataSource=Tools.ConvertDataReaderToDataTable(dr);
   dbOrders.DataBind();

   Double TotalPages = 1;//初始化,总页数为1
   Double ModePages=0;//取模余数(判断总页数是否要加1)
  
   Int32 TotalRecords = GetCountOrders();//调用上面的得到总记录数的方法
   TotalPages = TotalRecords / PageSize;//得到总页数(总记录数除以每页的记录数)
   ModePages=TotalRecords%PageSize;//得到取模的余数(总记录数取模每页的记录数)
   if(ModePages>0)//如果取模数不等于0,则把总页数加1
   {
    TotalPages+=1;
   }
   if(ModePages==0)//如果取模数等于0,不做任何事(也可以不用判断)
   {
   }

   lbTotalPage.Text = TotalPages.ToString();//显示页面上的总页数
   lbTotalCount.Text=TotalRecords.ToString();//显示页面上的总记录数

   //以下为判断点击的按钮(第一页,上一页,下一页,末一页)是否可以用
   if ( CurrentPageNumber == 1 )
   {
    PreviousPage.Enabled = false;
    FirstPage.Enabled=false;
    if ( TotalPages > 1 )
    {
     NextPage.Enabled = true;
     LastPage.Enabled=true;
    }
    else
    {
     NextPage.Enabled = false;
     LastPage.Enabled=false;
    }
   }
   else
   {
    PreviousPage.Enabled = true;
    FirstPage.Enabled=true;

    if ( CurrentPageNumber == TotalPages )
    {
     NextPage.Enabled = false;
     LastPage.Enabled=false;
    }
    else
    {
     NextPage.Enabled = true;
     LastPage.Enabled=true;
    }
   }

   ddlPage.Items.Clear();//清楚跳转的页数(如果不清除,里面的记录将会循环增加)
   int PCount=int.Parse(lbTotalPage.Text);//得到总页数,为了循环
   for(int i=1;i<=PCount;i++)
   {
    ddlPage.Items.Add(i.ToString());
   }
   ddlPage.Items.FindByText(CurrentPageNumber.ToString()).Selected=true;//把当前页显示在列表框的第一个
   
  }

  private void ddlPage_SelectedIndexChanged(object sender, System.EventArgs e)
  {
   int PageSize=int.Parse(ddlPage.SelectedValue.ToString());
   int PageCount=Int32.Parse(lbTotalPage.Text.Trim().ToString());
   if(PageSize<1)
   {
    CurrentPageNumber=1;
   }
   else if(PageSize>PageCount)
   {
    CurrentPageNumber=PageCount;
   }
   else
   {
    CurrentPageNumber=PageSize;
   }
   BindData();
  }

  private void btnGo_Click(object sender, System.EventArgs e)
  {
   int PageSize=int.Parse(txtPage.Text.Trim().ToString());
   int PageCount=Int32.Parse(lbTotalPage.Text.Trim().ToString());
   if(PageSize<1)
   {
    CurrentPageNumber=1;
   }
   else if(PageSize>PageCount)
   {
    CurrentPageNumber=PageCount;
   }
   else
   {
    CurrentPageNumber=PageSize;
   }
   BindData();
  }

  private void btnDelete_Click(object sender, System.EventArgs e)
  {
   try
   {
    string SelectedString = "";//定义一个变量
    foreach(DataGridItem data in dbOrders.Items)
    {
     for(int i=0;i<data.Cells[0].Controls.Count;i++)//循环DataGrid的第一个单元格
     {
      if(data.Cells[0].Controls[i].GetType().ToString()=="System.Web.UI.WebControls.CheckBox")//判断类型是否为CheckBox
      {
       if(((CheckBox)data.Cells[0].Controls[i]).Checked==true)//如果CheckBox被选中
       {
        SelectedString += dbOrders.DataKeys[data.ItemIndex].ToString() + ",";
        //因为设置了DataGrid的DataKeyField属性(编号),所以可以根据Datakeys得到选中CheckBox的那行所对应的那条记录的编号
        //以逗号分隔,加入同一个字符串中
       }
      }
     }
    }
    if(SelectedString!="")
    {
     bool result=true;
     SelectedString = SelectedString.Substring(0,SelectedString.Length-1);//截取最后一个逗号
     string[] Arr = SelectedString.Split(',');//分割字符串,放入数组中
     for(int i=0;i<Arr.Length;i++)//循环数组
     {
      if(Arr[i].Trim()!="")//如果值不为空
      {
       //result=CDG.DeleteOrder(Int32.Parse(arrselected[i]));//删除一条记录
       //这里的DeleteUser是我写的数据层的方法,返回的是bool,如果删除成功,返回true;
       //此处的删除方法可以根据自己的需求写,所以这里就不写了
      }
     }
     if(result)
     {
      Response.Write("<script>alert('用户删除成功')</script>");
    
     }
    }
    
    BindData();
   }
   catch
   {
    Response.Write("<script>alert('过程出现错误,删除失败,请查找原因')</script>");
   }
  }

  private void dbOrders_ItemDataBound(object sender, System.Web.UI.WebControls.DataGridItemEventArgs e)
  {
   if(e.Item.ItemType==ListItemType.Item)//这是判断属性生成器里添加的删除,弹出一个删除对话框
   {
    if(e.Item.ItemType==ListItemType.Item)//这个删除的事件在DeleteCommand中执行
    {
     LinkButton btn=(LinkButton)e.Item.Cells[7].Controls[0];
     btn.Attributes.Add ("onclick",
      "return confirm (\"确定要删除此项记录吗?\");");
    }
   }
   if(e.Item.ItemType==ListItemType.Item || e.Item.ItemType==ListItemType.AlternatingItem)//这是判断模板列中里添加的删除按钮(Button,ImageButton也可以),弹出一个删除对话框
   {
    Button button = (Button) e.Item.FindControl("btnADelete");//这个事件在ItemCommand事件中执行
    //ImageButton button = (ImageButton) e.Item.FindControl("Imagebutton1");
    button.Attributes.Add ("onclick",
     "return confirm (\"确定要删除此项记录吗?\");");
   }
  }

  private void dbOrders_DeleteCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
  {
   //写你的删除事件,下面是举例,具体根据自己的实际情况而定
   int OrderID=int.Parse(dbOrders.DataKeys[e.Item.ItemIndex].ToString());//得到该行的对应的编号
//   bool result=CDG.DeleteOrder(OrderID);
//   if(result)
//   {
//    Response.Write("<script>alert('用户删除成功')</script>");
//   }
  }

  private void dbOrders_ItemCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
  {
   int OrderID=int.Parse(dbOrders.DataKeys[e.Item.ItemIndex].ToString());//得到该行的对应的编号
   if(e.CommandName.Equals("Delete"))//此属性为设置的控件的CommandName,刚才设置的是Delete,表示删除(其他也可以)
   {
    //写你的删除事件,下面是举例,具体根据自己的实际情况而定
    //bool result=CDG.DeleteOrder(OrderID);
//    if(result)
//    {
//     Response.Write("<script>alert('用户删除成功')</script>");
//    }
   }
  }

 }
}