ASP.NET分页组件学与用——教学篇(源代码)

using System;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.ComponentModel;



using System.Text;



namespace NSLzhPages

{



public class LzhPages : System.Web.UI.WebControls.WebControl

{

private int _count;//每页显示的记录条数

private int _currentPage;//当前页

private int _allCount;//所有记录条数

private int _showPages;//显示页数



//以下脚本用于从文本框输入页码

private const string SCRIPTSTRING = "<script language=@#javascript@#>\n" +

" function go(ctrl,max)\n" +

" {\n" +

" if(ctrl.value >= 1 && ctrl.value <= max)\n" +

" {\n" +

" var url;\n" +

" var index;\n" +

" url = location.href;\n" +

" index = url.indexOf(@#?@#);\n" +

" if(index == -1)\n" +

" {\n" +

" }\n" +

" else\n" +

" {\n" +

" url = url.substring(0,index);\n" +

" }\n" +

" location.href = url + @#?currentPage=@# + ctrl.value;\n" +



" }\n" +

" else\n" +

" {\n" +

" alert(@#您输入的页码必须是符合页面要求的数字,最大值是：@# + max);\n" +

" return false;\n" +

" }\n" +

" }\n" +

"</script>\n";





[DefaultValue(10),Category("Customer")]

public int Count

{

set

{

if(value <= 0)

_count = 1;

else

_count = value;

}

get

{

return _count;

}

}



[DefaultValue(1),Category("Customer")]

public int CurrentPage

{

set

{

if(value < 0)

_currentPage = 1;

else

_currentPage = value;

}

get

{

return _currentPage;

}

}



[DefaultValue(1),Category("Customer")]

public int AllCount

{

get

{

return _allCount;

}

set

{

if(_allCount < 0)

throw new Exception("记录总条数不能为负数");

else

_allCount = value;

}

}



[DefaultValue(1),Category("Customer")]

public int Pages//总页数

{

get

{

if(this._allCount % this._count > 0)

return ((int)this._allCount / this._count) + 1;

else

return ((int)this._allCount / this._count);

}

}



[DefaultValue(1),Category("Customer")]

public int ShowPages

{

set

{

if(value > 0)

_showPages = value;

else

_showPages = 9;

}

get

{

return _showPages;

}

}



protected override void Render(HtmlTextWriter writer)

{

base.Render (writer);



string leftInfo;

StringBuilder centerInfo = new StringBuilder();



//分页条分三部分，leftInfo是最左边的部分，用来显示当前页/总页数，每页显示的记录条数

leftInfo = "页:" + this.CurrentPage.ToString() + "/" + this.Pages.ToString() + "&nbsp;&nbsp;" + "每页" + this.Count.ToString() + "条" + "&nbsp;&nbsp;共" + this.AllCount.ToString() + "条";



//中间的部分是分页部分

int min;//要显示的页面数最小值

int max;//要显示的页面数最大值



if(this.CurrentPage > this.Pages)//当前页必须小于最大页

{

this.CurrentPage = this.Pages;

}



if(this.CurrentPage % this.ShowPages == 0) //如果恰好整除

{

min = this.CurrentPage + 1;

max = this.CurrentPage + this.ShowPages ;

}

else if(this.CurrentPage % this.ShowPages == 1 && this.CurrentPage > this.ShowPages )

{

min = (((int)this.CurrentPage / this.ShowPages ) - 1) * this.ShowPages +1;

max = this.CurrentPage - 1;

}

else

{

min = ((int)this.CurrentPage / this.ShowPages) * this.ShowPages + 1;

max = (((int)this.CurrentPage / this.ShowPages) +1) * this.ShowPages;

}



string numberStr = "&nbsp;";//循环生成数字序列部分

string AbsUrl;//URL?左边的部分

AbsUrl = this.Context.Request.Url.ToString();

if(AbsUrl.IndexOf("?") == -1)

{

}

else

{

AbsUrl = AbsUrl.Substring(0,AbsUrl.IndexOf("?"));

}



for(int i = min ; i <= max ; i++)

{

if(i <= this.Pages)//只有不大于最大页才显示

{

if(this.CurrentPage == i)//如果是当前页，用斜体和红色显示

{

numberStr = numberStr + "<a href=" + AbsUrl + "?currentPage=" + i.ToString() + ">" + "<I style=@#color:red@#>" + i.ToString() + "</I>" +"</a>" + "\n";

}

else

{

numberStr = numberStr + "<a href=" + AbsUrl + "?currentPage=" + i.ToString() + ">" + i.ToString() +"</a>" + "\n";

}

}

}



//第一页，上一页，下一页,最后一页

string First,Previous,Next,Last;

First = AbsUrl + "?currentPage=1";

/////////

if(this.CurrentPage == 1)

Previous = AbsUrl + "?currentPage=1";

else

Previous = AbsUrl + "?currentPage=" + (this.CurrentPage - 1).ToString();

/////////

if(this.CurrentPage == this.Pages)

Next = AbsUrl + "?currentPage=" + this.Pages;

else

Next = AbsUrl + "?currentPage=" + (this.CurrentPage + 1).ToString();

/////////

Last = AbsUrl + "?currentPage=" + this.Pages;



centerInfo.AppendFormat("<font face=@#Webdings@# style=@#font-size:14px@#><a href={0}>7</a><a href={1}>3</a></font>{2}<font face=@#Webdings@# style=@#font-size:14px@#><a href={3}>4</a><a href={4}>8</a></font>",First,Previous,numberStr,Next,Last);



StringBuilder sb = new StringBuilder();//HTML字符串

sb.AppendFormat("<table style = @#font-size:12px@# border=@#0@# cellpadding=@#0@# cellspacing=@#0@# width=@#100%@#> \n " +

"<tr>\n" +

"<td width=@#25%@# align=@#left@#>{0}</td>\n" +

"<td width=@#61%@# align=@#right@#>{1}</td>\n" +

"<td width=@#14%@# align=@#right@#><input type=@#text@# name=@#T1@# size=@#4@# style=@#border-bottom:solid 1pt gray;border-top :solid 1pt gray; border-left:solid 1pt gray;border-right:solid 1pt gray;@#> \n <input type=@#button@# name=@#B1@# size=@#6@# value=go style=@#border-bottom:solid 1pt gray;border-top :solid 1pt gray; border-left:solid 1pt gray;border-right:solid 1pt gray;@# onclick=@#go(T1,{2})@#></td>\n" +

"</tr>\n" +

"</table>",leftInfo,

centerInfo.ToString(),

this.Pages);



writer.Write(sb.ToString());

}



protected override void OnPreRender(EventArgs e)

{

base.OnPreRender (e);

if(!Page.IsClientScriptBlockRegistered("WEREW-332DFAF-FDAFDSFDSAFD"))

{

Page.RegisterClientScriptBlock("WEREW-332DFAF-FDAFDSFDSAFD",SCRIPTSTRING);

}

}



}

}

原文转自：http://www.ltesting.net