分页控件是为页面数据分页导航显示的一个可重用控件。分页控件一般需要指定页码（PageIndex）、总记录数据（RecordCount）、页记录数（PageSize），可自动计算出页码数（PageCount）显示出来。如果使用客户端分页应该还要计算分页数据，下面我从如下几个方面来说分页控件。

一、GET和POST分页方式

GET和POST分页不同之处，在于传递分页参数的方式。GET分页使用URL地址附加参数方式，而POST则是在提交表单中设置分页参数，可以在页面中存放hidden控件。在ASP.NET中可以使用Postback，使用ViewState保存分页参数。一般在前台页面列表都是用GET方式分页，这样在URL中就包含了分页信息，有利于SEO搜索引擎收录，个人推荐使用GET方式在URL地址分页。

二、服务端分页和客户端分页

这里所说的服务端和客户端分页是指在设置列表数据源的方式不同来划分的。对于存在大量数据的情况下一般都会使用服务端分页，即在服务器端获取已分页的数据显示，需要显示第几页数据就从数据库中获取第几页的数据，在数据库中使用分页函数完成分页返回数据。客户端分页是指一次返回所有记录，再在服务器端中自行分页，在ASP.NET中可以使用PagedDataSource对象来分页，在指定数据源和页码后可以自动计算页数和分页。客户端分页只适应于数据量不大的情况下的分页。

三、自定义分页控件和用户控件分页

1.自定义分页控件

将分页控件做成通用的ASP.NET组件首选考虑使用自定义控件，这样每个页面将控件拖放过来就可以用。下面是我网站列表显示的一个URL分页控件，支持服务端分页和客户端分页，支持自定义输入页码数和显示记录条数。自定义分页控件代码如下：

自定义分页控件
  1using System;
  2using System.Collections.Generic;
  3using System.Text;
  4
  5using System.ComponentModel;
  6using System.Web;
  7using System.Web.UI;
  8using System.Web.UI.WebControls;
  9
 10
 11namespace Common.Control
 12...{
 13    public class Pager : System.Web.UI.Control, System.Web.UI.INamingContainer
 14    ...{
 15
 16        private int pageSize = 20;
 17
 18        [Description("页大小")]
 19        public int PageSize
 20        ...{
 21            get ...{
 22                this.SetPage();
 23                return this.pageSize; 
 24            }
 25            set ...{ pageSize = value; }
 26        }
 27
 28        private int pageIndex = 1;
 29
 30        [Description("页码")]
 31        public int PageIndex
 32        ...{
 33            get ...{
 34                this.SetPage();
 35                return pageIndex; 
 36            }
 37            set ...{ pageIndex = value; }
 38        }
 39
 40
 41        private bool isSetRecordCount = false;
 42
 43        private int recordCount = 0;
 44
 45        [Description("总记录数")]
 46        public int RecordCount
 47        ...{
 48            get ...{ return this.recordCount; }
 49            set
 50            ...{
 51                this.recordCount = value;
 52                this.isSetRecordCount = true;
 53
 54                this.SetPage();
 55            }
 56        }
 57
 58        private int pageCount = 0;
 59
 60        [Description("总页数")]
 61        public int PageCount
 62        ...{
 63            get ...{
 64                this.SetPage();
 65                return pageCount; 
 66            }
 67            set ...{ pageCount = value; }
 68        }
 69
 70        private int showPageCount = 10;
 71
 72        [Description("显示的页码数")]
 73        public int ShowPageCount
 74        ...{
 75            get ...{ return showPageCount; }
 76            set ...{ showPageCount = value; }
 77        }
 78
 79        private string cssClass;
 80
 81        [Description("样式类")]
 82        public string CssClass
 83        ...{
 84            get ...{ return cssClass; }
 85            set ...{ cssClass = value; }
 86        }
 87
 88        private string emptyData = "<div class=\"empty\">暂无数据</div>";
 89
 90        [Description("空数据时候呈现的内容")]
 91        public string EmptyData
 92        ...{
 93            get ...{ return emptyData; }
 94            set ...{ emptyData = value; }
 95        }
 96
 97        private bool showDivContainer = true;
 98
 99        [Description("显示包裹页码的DIV容器")]
100        public bool ShowDivContainer
101        ...{
102            get ...{ return showDivContainer; }
103            set ...{ showDivContainer = value; }
104        }
105
106        private bool showPageGo = false;
107
108        [Description("显示页面快速跳转表单")]
109        public bool ShowPageGo
110        ...{
111            get ...{ return showPageGo; }
112            set
113            ...{
114                this.showPageGo = value;
115                if (this.showPageGo)
116                    this.savePageSize = true;
117            }
118        }
119
120        private bool showFirstPage = true;
121
122        [Description("显示第一页")]
123        public bool ShowFirstPage
124        ...{
125            get ...{ return showFirstPage; }
126            set ...{ showFirstPage = value; }
127        }
128
129        private bool showLastPage = true;
130
131        [Description("显示最后一页")]
132        public bool ShowLastPage
133        ...{
134            get ...{ return showLastPage; }
135            set ...{ showLastPage = value; }
136        }
137
138        private string pageKey = "page";
139
140        [Description("页码查询字符串的Key")]
141        public string PageKey
142        ...{
143            get ...{ return pageKey; }
144            set ...{ pageKey = value; }
145        }
146
147        private string pageSizeKey = "pagesize";
148
149        [Description("显示记录数查询字符串的Key")]
150        public string PageSizeKey
151        ...{
152            get ...{ return pageSizeKey; }
153            set ...{ pageSizeKey = value; }
154        }
155
156        private bool savePageSize = false;
157
158        [Description("自动保存显示行数")]
159        public bool SavePageSize
160        ...{
161            get ...{ return savePageSize; }
162            set ...{ savePageSize = value; }
163        }
164
165        private bool saveQuery = true;
166
167        [Description("自动保存页面查询字符串")]
168        public bool SaveQuery
169        ...{
170            get ...{ return saveQuery; }
171            set ...{ saveQuery = value; }
172        }
173
174        private bool rawUrl = false;
175
176        [Description("使用原始URL路径")]
177        public bool RawUrl
178        ...{
179            get ...{ return rawUrl; }
180            set ...{ rawUrl = value; }
181        }
182
183        private string removeKey;
184
185        [Description("移除的字符串Keys")]
186        public string RemoveKey
187        ...{
188            get ...{ return removeKey; }
189            set ...{ removeKey = value; }
190        }
191
192        private void SetPage()
193        ...{
194            if (Context == null) return;
195
196            int pageindex = 1, pagesize = 20;
197            if (int.TryParse(Context.Request.QueryString[this.pageKey], out pageindex))
198            ...{
199                this.pageIndex = pageindex;
200            }
201            if (int.TryParse(Context.Request.QueryString[this.pageSizeKey], out pagesize) && pagesize > 0)
202            ...{
203                this.pageSize = pagesize;
204            }
205
206            this.pageCount = (int)Math.Ceiling(this.recordCount * 1.0 / this.pageSize);
207
208            if (this.pageIndex < 1)
209                this.pageIndex = 1;
210            if (this.pageIndex > this.pageCount && this.pageCount != 0)
211                this.pageIndex = this.pageCount;
212        }
213
214        /**//// <summary>
215        /// 设置分页的数据源，返回使用PagedDataSource客户端分页后的数据
216        /// </summary>
217        public PagedDataSource SetDataSource(System.Collections.IList dataSource)
218        ...{
219            if (dataSource == null) return null;
220
221            this.SetPage();
222            this.RecordCount = dataSource.Count;
223
224            PagedDataSource pds = new PagedDataSource();
225            pds.DataSource = dataSource;
226            pds.AllowPaging = true;
227            pds.CurrentPageIndex = this.pageIndex - 1;
228            pds.PageSize = this.pageSize;
229
230            return pds;
231            
232        }
233
234        protected override void Render(HtmlTextWriter writer)
235        ...{
236
237            if (Context == null)
238            ...{
239                writer.WriteLine("Pager");
240                return;
241            }
242
243            this.SetPage();
244
245            System.Text.StringBuilder sb = new System.Text.StringBuilder();
246
247            if (Context.Items.Contains("CurrentPath"))
248            ...{
249                sb.Append(Context.Items["CurrentPath"].ToString());
250            }
251            else if (this.rawUrl)
252            ...{
253                sb.Append(Context.Request.RawUrl.IndexOf("?") == -1 ? Context.Request.RawUrl : Context.Request.RawUrl.Substring(0, Context.Request.RawUrl.IndexOf("?")));
254            }
255            else
256            ...{
257                sb.Append(Context.Request.Path);
258            }
259            sb.Append("?");
260
261            if (this.savePageSize)
262            ...{
263                sb.AppendFormat("{0}={1}&", this.pageSizeKey, this.pageSize.ToString());
264            }
265
266            if (this.saveQuery)
267            ...{
268                for (int i = 0; i < Context.Request.QueryString.Count; i++)
269                ...{
270                    if (HttpContext.Current.Request.QueryString.Keys[i] != null
271                            && HttpContext.Current.Request.QueryString.Keys[i].ToLower() != this.pageSizeKey.ToLower()
272                            && HttpContext.Current.Request.QueryString.Keys[i].ToLower() != this.pageKey.ToLower()
273                            && !("," + this.removeKey + ",").Contains("," + HttpContext.Current.Request.QueryString.Keys[i] + ","))
274                        sb.AppendFormat("{0}={1}&", HttpContext.Current.Request.QueryString.Keys[i], HttpContext.Current.Request.QueryString[i]);
275                }
276            }
277            sb.AppendFormat("{0}=", pageKey);
278
279
280            if (this.recordCount <= 0) ...{
281                if (this.isSetRecordCount) ...{
282                    writer.WriteLine(this.emptyData);
283                }
284                return;
285            }
286
287            if (this.showDivContainer)
288            ...{
289                writer.WriteLine("<div class=\"" + (string.IsNullOrEmpty(this.cssClass) ? "pagination" : this.cssClass) + "\" id=\"" + this.ClientID + "\">");
290            }
291
292            if (this.showFirstPage && pageIndex > 1)
293            ...{
294                //if (pageIndex <= 1) {
295                //    writer.Write("<span class=\"disabled\"><<</span><span class=\"disabled\"><</span>");
296                //}
297                //else{
298                    writer.Write("<a title=\"第一页\" href=\"" + sb.ToString() + 1 + "\"><<</a>");
299                    writer.Write("<a title=\"上一页\" href=\"" + sb.ToString() + (pageIndex - 1).ToString() + "\"><</a>");
300                //} 
301            }
302
303            int startPage = this.pageIndex - this.showPageCount / 2;
304            int endPage = this.pageIndex + (this.showPageCount - 1) / 2;
305            if (startPage < 1)
306            ...{
307                endPage += 1 - startPage;
308                startPage = 1;
309            }
310            if (endPage > this.pageCount)
311            ...{
312                startPage -= endPage - this.pageCount;
313                if (startPage < 1) startPage = 1;
314                endPage = this.pageCount;
315            }
316
317            if (this.pageCount > 1)
318            ...{
319                for (int i = startPage; i <= endPage; i++)
320                ...{
321                    if (i == pageIndex)
322                        writer.Write("<span class=\"current\">" + i + "</span>");
323                    else
324                        writer.Write("<a title=\"第" + i + "页\" href=\"" + sb.ToString() + i.ToString() + "\">" + i + "</a>");
325                }
326            }
327
328            if (this.showLastPage && pageIndex < pageCount)
329            ...{
330                //if (pageIndex >= pageCount) {
331                //    writer.Write("<span class=\"disabled\">></span><span class=\"disabled\">>></span>");
332                //}
333                //else {
334                    writer.Write("<a title=\"下一页\" href=\"" + sb.ToString() + (pageIndex + 1).ToString() + "\">></a>");
335                    writer.Write("<a title=\"最后一页\" href=\"" + sb.ToString() + this.pageCount + "\">>></a>");
336                //}
337            }
338
339            if (this.ShowPageGo)
340            ...{
341                string locationRedirect = "location='" + sb.ToString() + "'+this.previousSibling.value;";
342                if (this.savePageSize)
343                ...{
344                    locationRedirect = "location='" + sb.ToString().Replace(this.pageSizeKey + "=" + this.pageSize.ToString() + "&", this.pageSizeKey + "='+this.previousSibling.previousSibling.previousSibling.value+'&") + "'+this.previousSibling.value;";
345                }
346
347                writer.WriteLine();
348                writer.Write("<form method=\"get\" action=\"" + sb.ToString() + this.pageIndex.ToString() + "\">");
349                writer.Write("<span class=\"page\" onkeypress=\"return function (e){e=window.event||e;var num=e.which?e.which:e.keyCode;if(num==13){this.lastChild.onclick();return false;}}\">显示行：<input type=\"text\" name=\"" + this.pageSizeKey + "\" title=\"输入按回车跳转\" size=\"4\" value=\"" + this.pageSize + "\" class=\"text\" />/" + this.recordCount + "，跳转：<input type=\"text\" name=\"" + this.pageKey + "\" title=\"输入按回车跳转\" size=\"4\" value=\"" + this.pageIndex + "\" class=\"text\" /><input type=\"submit\" class=\"btn\" onclick=\"" + locationRedirect + "return false;\" value=\"Go\" /></span>");
350                writer.WriteLine("</form>");
351
352            }
353
354            if (this.showDivContainer)
355            ...{
356                writer.Write("</div>");
357            }
358
359        }
360
361    }
362
363}

2.用户控件分页

分页控件同样可以做成ASCX用户控件，这样在每个页面注册控件，和自定义控件使用差不多。下面是一个使用Post方式的分页用户控件，使用了分页事件、视图状态等，代码如下：

Pager.ascx
 1<%...@ Control Language="C#" AutoEventWireup="true" CodeBehind="Pager.ascx.cs" Inherits="Common.Inc.Pager" %>
 2
 3<table width="100%">
 4    <tr>
 5        <td align="right">
 6            
 7        <asp:Label ID="Labeldata" runat="server" ForeColor="Red"></asp:Label>
 8        
 9        <asp:Label ID="lblRecordCount" runat="server" Text="记录数"></asp:Label>
10        
11        &nbsp;&nbsp;
12        
13        <asp:LinkButton ID="lnkbtnFirst" CommandName="First" runat="server" OnClick="PagerButtonClick">首页</asp:LinkButton>&nbsp;
14        <asp:LinkButton ID="lnkbtnPrev" CommandName="Pre" runat="server" OnClick="PagerButtonClick">上一页</asp:LinkButton>&nbsp;
15        <asp:LinkButton ID="lnkbtnNext" CommandName="Next" runat="server" OnClick="PagerButtonClick">下一页</asp:LinkButton>&nbsp;
16        <asp:LinkButton ID="lnkbtnLast" CommandName="Last" runat="server" OnClick="PagerButtonClick">尾页</asp:LinkButton>&nbsp;
17        &nbsp;&nbsp;
18        <asp:TextBox ID="txtJumpPage" runat="server" Text="1" Width="38px" ValidationGroup="vgSkip" />
19        <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="txtJumpPage"
20                                Display="Dynamic" ErrorMessage="请输入跳转的页数!" ValidationGroup="vgSkip"></asp:RequiredFieldValidator>
21        <asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="txtJumpPage"
22            Display="Dynamic" ErrorMessage="页数只能为正数!" ValidationExpression="\d*" ValidationGroup="vgSkip"></asp:RegularExpressionValidator>
23        <asp:LinkButton ID="lnkbtnJumpPage" runat="server" OnClick="lnkbtnJumpPage_Click" ValidationGroup="vgSkip">跳转</asp:LinkButton>
24           
25        </td>
26    </tr>
27</table>

Pager.ascx.cs
  1using System;
  2using System.Collections.Generic;
  3using System.Linq;
  4using System.Web;
  5using System.Web.UI;
  6using System.Web.UI.WebControls;
  7using System.Collections;
  8
  9namespace Common.Inc
 10...{
 11
 12
 13    public partial class Pager : System.Web.UI.UserControl
 14    ...{
 15
 16        private string emptyDataText = "暂时没有数据!";
 17        public string EmptyDataText
 18        ...{
 19            get ...{ return emptyDataText; }
 20            set ...{ emptyDataText = value; }
 21        }
 22
 23        private int pageSize = 10;
 24        public int PageSize 
 25        ...{
 26            get ...{ return pageSize; }
 27            set ...{ pageSize = value; }
 28        }
 29
 30        private int recordCount = -1;
 31        public int RecordCount
 32        ...{
 33            get ...{ return recordCount; }
 34            set
 35            ...{
 36                recordCount = value;
 37                RenderPager();
 38            }
 39        }
 40
 41        public int PageIndex 
 42        ...{
 43            get
 44            ...{
 45                string stateBagName = "PageIndex" + this.UniqueID;
 46                if (ViewState[stateBagName] == null)
 47                    return 0;
 48                else
 49                    return int.Parse(ViewState[stateBagName].ToString()); 
 50            } 
 51            set 
 52            ...{
 53                string stateBagName = "PageIndex" + this.UniqueID;
 54                ViewState[stateBagName] = value.ToString();
 55            }
 56        }
 57
 58        public int PageCount
 59        ...{
 60            get
 61            ...{
 62                string stateBagName = "PageCount" + this.UniqueID;
 63                if (ViewState[stateBagName] == null)
 64                    return 0;
 65                else
 66                    return int.Parse(ViewState[stateBagName].ToString());
 67            }
 68            set
 69            ...{
 70                string stateBagName = "PageCount" + this.UniqueID;
 71                ViewState[stateBagName] = value.ToString();
 72            }
 73        }
 74
 75        
 76
 77        //
 78        // 摘要:
 79        //     在单击某一页导航按钮时发生。
 80        public event PagerEventHandler PageIndexChanging;
 81
 82        /**//// <summary>
 83        /// 分页对象
 84        /// </summary>
 85        public PagedDataSource PagerDataSource;
 86
 87
 88        public PagedDataSource SetPager(IEnumerable source)
 89        ...{
 90            PagerDataSource = new PagedDataSource();
 91            
 92            PagerDataSource.AllowPaging = true;
 93
 94            PagerDataSource.DataSource = source;
 95            PagerDataSource.PageSize = PageSize;
 96            PagerDataSource.CurrentPageIndex = PageIndex;
 97
 98            this.RecordCount = PagerDataSource.DataSourceCount;
 99            
100            return PagerDataSource;
101        }
102
103
104        /**//// <summary>
105        /// 分页的相关参数设置
106        /// </summary>
107        protected void RenderPager()
108        ...{
109            this.PageCount = (int)Math.Ceiling(RecordCount * 1.0 / PageSize);
110
111            bool resetPageIndex = false;
112            if (PageIndex < 0)
113            ...{
114                this.PageIndex = 0;
115                resetPageIndex = true;
116            }
117            if (PageIndex >= PageCount && PageCount>0)
118            ...{
119                this.PageIndex = PageCount - 1;
120                resetPageIndex = true;
121            }
122            if (PagerDataSource != null && resetPageIndex == true)
123            ...{
124                PagerDataSource.CurrentPageIndex = PageIndex;
125            }
126
127            lnkbtnFirst.Visible = PageCount > 1;
128            lnkbtnPrev.Visible = PageCount > 1;
129            lnkbtnNext.Visible = PageCount > 1;
130            lnkbtnLast.Visible = PageCount > 1;
131
132            lnkbtnJumpPage.Visible = PageCount > 1;
133
134            txtJumpPage.Visible = PageCount > 1;
135            txtJumpPage.Text = (PageIndex + 1).ToString();
136                        
137            lblRecordCount.Text = "记录数" + RecordCount.ToString() + " 条";
138            lblRecordCount.Visible = RecordCount > 0;
139            Labeldata.Text = RecordCount > 0 ? string.Empty : EmptyDataText;
140
141            lnkbtnFirst.Enabled = lnkbtnPrev.Enabled = PageIndex > 0;
142            lnkbtnNext.Enabled = lnkbtnLast.Enabled = PageIndex < PageCount - 1;
143            
144        }
145
146
147        /**//// <summary>
148        /// 跳转到指定页面，页面参数由输入控件获取
149        /// </summary>
150        /// <param name="sender"></param>
151        /// <param name="e"></param>
152        protected void lnkbtnJumpPage_Click(object sender, EventArgs e)
153        ...{
154
155            int newPageIndex = int.Parse(txtJumpPage.Text) - 1;
156
157            OnPageIndexChanging(new PagerEventArgs(newPageIndex));
158        }
159
160
161        /**//// <summary>
162        /// 首页，上一页，下一页，尾页公用的点击程序
163        /// </summary>
164        /// <param name="sender"></param>
165        /// <param name="e"></param>
166        protected void PagerButtonClick(object sender, EventArgs e)
167        ...{
168            int newPageIndex = 0;
169            string commandName = ((LinkButton)sender).CommandName;
170            switch(commandName)
171            ...{
172                case "First":
173                    newPageIndex=0;
174                    break;
175                case "Pre":
176                    newPageIndex = PageIndex-1;
177                    break;
178                case "Next":
179                    newPageIndex = PageIndex+1;
180                    break;
181                case "Last":
182                    newPageIndex = PageCount - 1;
183                    break;
184            }
185
186            OnPageIndexChanging(new PagerEventArgs(newPageIndex));
187
188        }
189
190        protected virtual void OnPageIndexChanging(PagerEventArgs e)
191        ...{
192            if (this.PageIndexChanging == null)
193                throw new HttpException("Pager“" + ID + "”激发了未处理的事件“PageIndexChanging”。 ");
194            
195            this.PageIndexChanging(this, e);
196        }
197
198
199    }
200
201    
202    public delegate void PagerEventHandler(object sender, PagerEventArgs e);
203
204    public class PagerEventArgs : System.ComponentModel.CancelEventArgs
205    ...{
206
207        public PagerEventArgs(int newPageIndex)
208        ...{
209            this.NewPageIndex = newPageIndex;
210        }
211
212        public int NewPageIndex ...{ get; set; }
213    }
214
215
216}

ASP.NET分页控件使用请参见：在线分页控件使用示例