/****************************************************************** 
** 文件名:Pager.cs 
** 創建人:楊響武 
** 日 期:2005年7月27日 
** 修改人: 
** 日 期: 
** 描 述: 
** 
**---------------------------------------------------------------- 
******************************************************************/ 

using System; 
using System.Web.UI.WebControls; 
using System.Web.UI.HtmlControls; 
using System.Web; 
using System.Web.UI; 
using System.Text.RegularExpressions; 

namespace MyCompany.Controls 
{ 
/// <summary> 
/// 分頁控件 
/// </summary> 
public class Pager : Label, INamingContainer 
{ 
#region 成員變量和構造函數 
HttpContext context = HttpContext.Current; 
Label countLabel; 
HyperLink previousButton; 
HyperLink nextButton; 
HyperLink firstButton; 
HyperLink lastButton; 
HyperLink[] pagingLinkButtons; 

public override ControlCollection Controls 
{ 
get 
{ 
EnsureChildControls(); 
return base.Controls; 
} 
} 

protected override void CreateChildControls() 
{ 
Controls.Clear(); 

AddCountLabel(); 

AddPageButtons(); 

AddPreviousNextHyperLinks(); 

AddFirstLastHyperLinks(); 
} 
#endregion 

#region 呈現方法 
protected override void Render(HtmlTextWriter writer) 
{ 
// 修改總頁數小于等于1的時候不呈現任何控件 
// int totalPages = CalculateTotalPages(); 
// 
// if (totalPages <= 1) 
// return; 

AddAttributesToRender(writer); 

writer.AddAttribute(HtmlTextWriterAttribute.Class, this.CssClass, false); 

RenderCountLabel(writer); 

RenderFirst(writer); 

RenderPrevious(writer); 

RenderPagingButtons(writer); 

RenderNext(writer); 

RenderLast(writer); 
} 

void RenderCountLabel(HtmlTextWriter writer) 
{ 
countLabel.RenderControl(writer); 

LiteralControl l = new LiteralControl(" "); 
l.RenderControl(writer); 
} 

void RenderFirst (HtmlTextWriter writer) 
{ 
firstButton.RenderControl(writer); 

LiteralControl l = new LiteralControl(" "); 
l.RenderControl(writer); 
} 

void RenderLast (HtmlTextWriter writer) 
{ 
lastButton.RenderControl(writer); 

LiteralControl l = new LiteralControl(" "); 
l.RenderControl(writer); 
} 

void RenderPrevious (HtmlTextWriter writer) 
{ 
previousButton.RenderControl(writer); 

LiteralControl l = new LiteralControl(" "); 
l.RenderControl(writer); 
} 

void RenderNext(HtmlTextWriter writer) 
{ 
nextButton.RenderControl(writer); 

LiteralControl l = new LiteralControl(" "); 
l.RenderControl(writer); 
} 

private void RenderButtonRange(int start, int end, HtmlTextWriter writer) 
{ 
for (int i = start; i < end; i++) 
{ 
if (PageIndex == i) 
{ 
Literal l = new Literal(); 
l.Text = "<font color =red>" + (i + 1).ToString() + "</font>"; 

l.RenderControl(writer); 
} 
else 
{ 
pagingLinkButtons.RenderControl(writer); 
} 
if (i < (end - 1)) 
writer.Write(" "); 
} 

LiteralControl l1 = new LiteralControl(" "); 
l1.RenderControl(writer); 
} 

private void RenderPagingButtons(HtmlTextWriter writer) 
{ 
int totalPages; 

totalPages = CalculateTotalPages(); 

if (totalPages <= 10) 
{ 
RenderButtonRange(0, totalPages, writer); 
} 
else 
{ 
int lowerBound = (PageIndex - 4); 
int upperBount = (PageIndex + 6); 

if (lowerBound <= 0) 
lowerBound = 0; 

if (PageIndex <= 4) 
RenderButtonRange(0, 10, writer); 

else if (PageIndex < (totalPages - 5)) 
RenderButtonRange(lowerBound, (PageIndex + 6), writer); 

else if (PageIndex >= (totalPages - 5)) 
RenderButtonRange((totalPages - 10), totalPages, writer); 
} 
} 

#endregion 

#region 控件樹方法 
/// <summary> 
/// 信息標簽 
/// </summary> 
void AddCountLabel() 
{ 
countLabel = new Label(); 
countLabel.ID = "countLabel"; 
countLabel.Text = string.Format(text, CalculateTotalPages().ToString("n0")); 

Controls.Add(countLabel); 
} 

private void AddPageButtons() 
{ 
pagingLinkButtons = new HyperLink[CalculateTotalPages()]; 

for (int i = 0; i < pagingLinkButtons.Length; i++) 
{ 
pagingLinkButtons = new HyperLink(); 
pagingLinkButtons.EnableViewState = false; 
pagingLinkButtons.Text = (i + 1).ToString(); 
pagingLinkButtons.ID = i.ToString(); 
pagingLinkButtons.CssClass = linkCss; 
pagingLinkButtons.NavigateUrl = GetHrefString(i); 

Controls.Add(pagingLinkButtons); 
} 
} 

/// <summary> 
/// 首頁末頁 
/// </summary> 
void AddFirstLastHyperLinks() 
{ 
firstButton = new HyperLink(); 
firstButton.ID = "First"; 
firstButton.Text = "首頁"; 
if(PageIndex != 0 && CalculateTotalPages() > 0) 
{ 
firstButton.NavigateUrl = GetHrefString(0); 
} 
else 
{ 
firstButton.Enabled = false; 
} 

Controls.Add(firstButton); 

lastButton = new HyperLink(); 
lastButton.ID = "Last"; 
lastButton.Text = "末頁"; 
if(PageIndex != CalculateTotalPages() - 1) 
{ 
lastButton.NavigateUrl = GetHrefString(CalculateTotalPages() - 1); 
} 
else 
{ 
lastButton.Enabled = false; 
} 
Controls.Add(lastButton); 
} 

/// <summary> 
/// 上一頁下一頁 
/// </summary> 
void AddPreviousNextHyperLinks() 
{ 
previousButton = new HyperLink(); 
previousButton.ID = "Prev"; 
previousButton.Text = "上一頁"; 
if (HasPrevious) 
{ 
previousButton.NavigateUrl = GetHrefString(PageIndex - 1); 
} 
else 
{ 
previousButton.Enabled = false; 
} 
Controls.Add(previousButton); 

nextButton = new HyperLink(); 
nextButton.ID = "Next"; 
nextButton.Text = "下一頁"; 
if(HasNext) 
{ 
nextButton.NavigateUrl = GetHrefString(PageIndex + 1); 
} 
else 
{ 
nextButton.Enabled = false; 
} 
Controls.Add(nextButton); 
} 
#endregion 

#region 私有屬性 
private bool HasPrevious 
{ 
get 
{ 
if (PageIndex > 0) 
return true; 

return false; 
} 
} 

private bool HasNext 
{ 
get 
{ 
if (PageIndex + 1 < CalculateTotalPages() ) 
return true; 

return false; 
} 
} 
#endregion 

#region 幫助方法和公共屬性 

/// <summary> 
/// 獲取分頁導航按鈕的超鏈接字符串 
/// </summary> 
/// <param name="pageIndex">該分頁按鈕相對應的頁索引</param> 
/// <returns>分頁導航按鈕的超鏈接字符串</returns> 
private string GetHrefString(int pageIndex) 
{ 
string url = Page.Request.RawUrl; 

if (Regex.IsMatch(url, @"(/d+).shtml", RegexOptions.IgnoreCase)) 
{ 
url = Regex.Replace(url, @"(/d+).shtml", pageIndex + ".shtml"); 
} 

if (Regex.IsMatch(url, @"PageIndex=(/d+)", RegexOptions.IgnoreCase)) 
{ 
url = Regex.Replace(url, @"PageIndex=(/d+)", "PageIndex=" + pageIndex.ToString()); 
} 

return Page.Server.UrlPathEncode(url); 
} 

public int CalculateTotalPages() 
{ 
int totalPagesAvailable; 

if (TotalRecords == 0) 
return 0; 

totalPagesAvailable = TotalRecords / PageSize; 

if ((TotalRecords % PageSize) > 0) 
totalPagesAvailable++; 

return totalPagesAvailable; 
} 

/// <summary> 
/// 當前頁 
/// </summary> 
public int PageIndex 
{ 
get 
{ 
int _pageIndex = 0; 

if ((!Page.IsPostBack) && (context.PageIndex > 0)) 
_pageIndex = context.PageIndex; 
else 
_pageIndex = Convert.ToInt32(ViewState["PageIndex"]); 

if (_pageIndex < 0) 
return 0; 
else 
{ 
if (_pageIndex > CalculateTotalPages()-1) 
return CalculateTotalPages()-1; 
else 
return _pageIndex; 
} 
} 
set 
{ 
ViewState["PageIndex"] = value; 
} 
} 

/// <summary> 
/// 每頁記錄數 
/// </summary> 
public int PageSize 
{ 
get 
{ 
int pageSize = Convert.ToInt32(ViewState["PageSize"]); 

if (pageSize == 0) 
{ 
return 10; 
} 

return pageSize; 
} 
set 
{ 
ViewState["PageSize"] = value; 
} 

} 

/// <summary> 
/// 總記錄數 
/// </summary> 
public int TotalRecords 
{ 
get 
{ 
return Convert.ToInt32(ViewState["TotalRecords"]); 
} 
set 
{ 
ViewState["TotalRecords"] = value; 
} 
} 

private string text = "共{0}頁"; 

private string linkCss = ""; 
/// <summary> 
/// 鏈接樣式 
/// </summary> 
public string LinkCss 
{ 
get { return linkCss; } 
set { linkCss = value;} 
} 

private string textCss = ""; 
/// <summary> 
/// 文字樣式 
/// </summary> 
public string TextCss 
{ 
get { return textCss; } 
set { textCss = value;} 
} 

public string TextFormat 
{ 
get 
{ 
return text; 
} 
set 
{ 
text = value; 
} 
} 

#endregion 
} 
} 

<%@ Control Language="c#" %> 
<%@ Register TagPrefix="Anchor" Namespace="MyCompany.Controls" Assembly="MyCompany.Controls" %> 
<ANCHOR:PAGER id="Pager1" runat="server"></ANCHOR:PAGER>