ASP.NET中的分页剖析(四)-知识库

文章类型：	.NET
关键词：	C#,ASPX,ASP,.NET中,分页,自定义
内容摘要：

ASP.NET中的分页剖析(四)

2015/7/29 12:23:43 来源：apple 阅读：

这里我们把前面的代码重构为用户控件的方式来使用，提高代码的利用率。

用户控件PagerControl.ascx的页面的设计图如下：

用户控件PagerControl.ascx的页面代码如下：

<%@ Control Language="C#" AutoEventWireup="true" CodeFile="PagerControl.ascx.cs" Inherits="_Controls_PagerControl" %>

<asp:Label ID="lblMessage" runat="server" Text="msg" Height="25px" Font-Size="15" ></asp:Label> 

<asp:Button ID="btnFirstPage" runat="server" Text="首页" Width="48px"

Height="25px" onclick="btnFirstPage_Click" /> 

<asp:Button ID="btnPreviousPage" runat="server" Text="上一页" Width="48px"

Height="25px" onclick="btnPreviousPage_Click" /> 

<asp:Button ID="btnNextPage" runat="server" Text="下一页" Width="48px"

Height="25px" onclick="btnNextPage_Click" /> 

<asp:Button ID="btnLastPage" runat="server" Text="末页" Width="48px"

Height="25px" onclick="btnLastPage_Click" /> 

<asp:TextBox ID="txtPageSize" runat="server" Width="25px" Height="25px"></asp:TextBox>

<asp:RequiredFieldValidator ID="rfvTxtPageSize" runat="server"

ControlToValidate="txtPageSize" ErrorMessage="页面记录大小不能为空！">*</asp:RequiredFieldValidator>

<asp:RangeValidator ID="rvTxtPageSize" runat="server"

ControlToValidate="txtPageSize" ErrorMessage="页面记录大小必须大于零且不大于当前记录数！"

MinimumValue="1" Type="Integer">*</asp:RangeValidator>

跳到:</span>

<asp:TextBox ID="txtCurrentPageIndex" runat="server" Width="25px" Height="25px"></asp:TextBox>

<asp:RequiredFieldValidator ID="rfvTxtCPI" runat="server"

ControlToValidate="txtCurrentPageIndex" ErrorMessage="跳转页不能为空！">*</asp:RequiredFieldValidator>

<asp:RangeValidator ID="rvTxtCPI" runat="server" BorderStyle="None"

ControlToValidate="txtCurrentPageIndex" ErrorMessage="输入页必须大于零且不大于当前页面数！"

MinimumValue="1" Type="Integer">*</asp:RangeValidator>

页</span>

<asp:Button ID="btnTurnPage" runat="server" Text="GO" Width="25px"

Height="25px" onclick="btnTurnPage_Click" />

<asp:ValidationSummary ID="ValidationSummary1" runat="server"

ShowMessageBox="True" ShowSummary="False" />

</div>

对应的PagerControl.ascx.cs业务逻辑文件代码如下：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

public partial class _Controls_PagerControl : System.Web.UI.UserControl

{

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

rvTxtPageSize.MaximumValue = RecordCount.ToString();

rvTxtCPI.MaximumValue = PageCount.ToString();

SetCurrentStatus();

}

else

{

rvTxtPageSize.MaximumValue = RecordCount.ToString();

rvTxtCPI.MaximumValue = PageCount.ToString();

}

/// <summary>

/// 页面是否改变

/// </summary>

private bool pagerChanged = false;

public bool PagerChanged

{

get { return pagerChanged; }

set { pagerChanged = value; }

}

/// <summary>

/// 当前页索引号

/// </summary>

public int Pager

{

get { return (int)ViewState["Page"]; }

set { ViewState["Page"] = value; }

}

/// <summary>

/// 分页大小

/// </summary>

public int PageSize

{

get { return (int)ViewState["PageSize"]; }

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

}

/// <summary>

/// 记录数量

/// </summary>

public int RecordCount

{

get

{

return (int)ViewState["RecordCount"];

}

set

{

ViewState["RecordCount"] = value;

}

/// <summary>

/// 总页数

/// </summary>

public int PageCount

{

get

{

return (int)Math.Ceiling((double)RecordCount / PageSize);

}

protected void btnFirstPage_Click(object sender, EventArgs e)

{

pagerChanged = true;

PageSize = Convert.ToInt32(txtPageSize.Text.Trim());

Pager = 1;

SetCurrentStatus();

}

protected void btnPreviousPage_Click(object sender, EventArgs e)

{

pagerChanged = true;

PageSize = Convert.ToInt32(txtPageSize.Text.Trim());

Pager--;

SetCurrentStatus();

}

protected void btnNextPage_Click(object sender, EventArgs e)

{

pagerChanged = true;

PageSize = Convert.ToInt32(txtPageSize.Text.Trim());

Pager++;

SetCurrentStatus();

}

protected void btnLastPage_Click(object sender, EventArgs e)

{

pagerChanged = true;

PageSize = Convert.ToInt32(txtPageSize.Text.Trim());

Pager = PageCount;

SetCurrentStatus();

}

protected void btnTurnPage_Click(object sender, EventArgs e)

{

pagerChanged = true;

Pager = Convert.ToInt32(txtCurrentPageIndex.Text.Trim());

PageSize = Convert.ToInt32(txtPageSize.Text.Trim());

SetCurrentStatus();

}

private void SetCurrentStatus()

{

if (Pager == 1 && Pager == PageCount)

{

btnFirstPage.Enabled = false;

btnPreviousPage.Enabled = false;

btnNextPage.Enabled = false;

btnLastPage.Enabled = false;

}

else

{

if (Pager == 1)

{

btnFirstPage.Enabled = false;

btnPreviousPage.Enabled = false;

btnNextPage.Enabled = true;

btnLastPage.Enabled = true;

}

else if (Pager == PageCount)

{

btnFirstPage.Enabled = true;

btnPreviousPage.Enabled = true;

btnNextPage.Enabled = false;

btnLastPage.Enabled = false;

}

else

{

btnFirstPage.Enabled = true;

btnPreviousPage.Enabled = true;

btnNextPage.Enabled = true;

btnLastPage.Enabled = true;

}

txtCurrentPageIndex.Text = Pager.ToString();

txtPageSize.Text = PageSize.ToString();

lblMessage.Text = "当前页：" + Pager + "共" + PageCount + "页";

}

使用分页用户控件的.aspx页面代码如下：

<%@ Register src="_Controls/PagerControl.ascx" tagname="PagerControl" tagprefix="uc1" %>

<uc1:PagerControl ID="PagerControl1" runat="server" />

</div>

使用分页用户控件的.aspx.cs业务逻辑文件代码如下：

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using MyBookShop.BLL;

using MyBookShop.Models;

using System.Collections.Generic;

using System.Drawing;

public partial class BookList_UserPagerControl : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

//首次加载，赋初值

try

{

ViewState["typeid"] = Convert.ToInt32(Request.QueryString["typeid"]);

}

catch

{

ViewState["typeid"] = -1;

}

this.PagerControl1.RecordCount = BookManager.GetBooksCountByCategoryId(Convert.ToInt32(ViewState["typeid"]));

btnChangeOrder.Enabled = false;

this.PagerControl1.Pager = 1;

this.PagerControl1.PageSize = 10;

BindData();

}

/// <summary>

/// 获得封面的url

/// </summary>

/// <param name="isbn"></param>

/// <returns></returns>

public string GetUrl(string isbn)

{

return StringHandler.CoverUrl(isbn);

}

/// <summary>

/// 截断图书显示内容

/// </summary>

/// <param name="content"></param>

/// <param name="num"></param>

/// <returns></returns>

public string GetCut(string content, int num)

{

return StringHandler.CutString(content, num);

}

#region 排序

protected void btnDate_Click(object sender, EventArgs e)

{

if (btnPrice.Enabled)

{

btnPrice.Enabled = false;

btnPrice.BackColor = Color.Gray;

if (!btnChangeOrder.Enabled)

{

btnChangeOrder.Enabled = true;

}

string publishDateOrder = (string)ViewState["Order"];

if (publishDateOrder == null)

{

ViewState["Order"] = "PublishDate";

btnDate.Text = "出版日期↑";

}

else

{

if (publishDateOrder.Equals("PublishDate"))

{

ViewState["Order"] = "PublishDate Desc";

btnDate.Text = "出版日期↓";

}

else

{

ViewState["Order"] = "PublishDate";

btnDate.Text = "出版日期↑";

}

this.PagerControl1.Pager = 1;

BindData();

}

protected void btnPrice_Click(object sender, EventArgs e)

{

if (btnDate.Enabled)

{

btnDate.Enabled = false;

btnDate.BackColor = Color.Gray;

if (!btnChangeOrder.Enabled)

{

btnChangeOrder.Enabled = true;

}

string unitPriceOrder = (string)ViewState["Order"];

if (unitPriceOrder == null)

{

ViewState["Order"] = "UnitPrice";

btnPrice.Text = "价格↑";

}

else

{

if (unitPriceOrder.Equals("UnitPrice"))

{

ViewState["Order"] = "UnitPrice Desc";

btnPrice.Text = "价格↓";

}

else

{

ViewState["Order"] = "UnitPrice";

btnPrice.Text = "价格↑";

}

this.PagerControl1.Pager = 1;

BindData();

}

#endregion

private void BindData()

{

int currentPageIndex = this.PagerControl1.Pager;

int pageSize = this.PagerControl1.PageSize;

IList<Book> books;

if (this.PagerControl1.Pager == this.PagerControl1.PageCount)

{

books = BookManager.GetCurrentPageBooksByCategoryId((currentPageIndex - 1) * pageSize + 1, this.PagerControl1.RecordCount, Convert.ToInt32(ViewState["typeid"]), (string)ViewState["Order"]);

}

else

{

books = BookManager.GetCurrentPageBooksByCategoryId((currentPageIndex - 1) * pageSize + 1, currentPageIndex * pageSize, Convert.ToInt32(ViewState["typeid"]), (string)ViewState["Order"]);

}

dlBooks.DataSource = books;

dlBooks.DataBind();

}

protected void btnChangeOrder_Click(object sender, EventArgs e)

{

if (btnDate.Enabled)

{

btnDate.Enabled = false;

btnDate.BackColor = Color.Gray;

}

else

{

btnDate.Enabled = true;

btnDate.BackColor = Color.FromArgb(192, 255, 192);

if (btnDate.Text.Trim().Equals("出版日期↑"))

{

ViewState["Order"] = "PublishDate";

}

else

{

ViewState["Order"] = "PublishDate Desc";

}

this.PagerControl1.Pager = 1;

BindData();

}

if (btnPrice.Enabled)

{

btnPrice.Enabled = false;

btnPrice.BackColor = Color.Gray;

}

else

{

btnPrice.Enabled = true;

btnPrice.BackColor = Color.FromArgb(192, 255, 192);

if (btnPrice.Text.Trim().Equals("价格↑"))

{

ViewState["Order"] = "UnitPrice";

}

else

{

ViewState["Order"] = "UnitPrice Desc";

}

this.PagerControl1.Pager = 1;

BindData();

}

protected void dlBooks_PreRender(object sender, EventArgs e)

{

if (this.PagerControl1.PagerChanged)

{

this.PagerControl1.PagerChanged = false;

this.PagerControl1.RecordCount = BookManager.GetBooksCountByCategoryId(Convert.ToInt32(ViewState["typeid"]));

BindData();

}

DAL获得记录数量方法代码如下：

public static int GetBooksCountByCategoryId(int categoryId)

{

string sql = string.Empty;

if (categoryId > 0)

{

sql = "select count(*) from Books where CategoryId=" + categoryId;

}

else

{

sql = "select count(*) from Books";

}

int bookCount = DBHelper.GetScalar(sql);

return bookCount;

}

好了，这一篇就到这里吧！这几篇的叙述少了些，源码多了些，相信大家对这些代码能够看懂，有什么不懂的地方给我留言吧！下一篇准备把基于SQL语句的数据获取方式重构为存储过程来实现。【待续...】

↑ 上一篇文章：ASP.NET中的分页剖析(三) 关键词：C#,ASPX,ASP,.NET中,分页,自定义发布日期：2015/7/29 12:22:15
↓ 下一篇文章：ASP.NET中的分页剖析(五) 关键词：C#,ASPX,ASP,.NET中,分页,自定义发布日期：2015/7/29 12:24:24

相关文章：
ASP.NET中的分页剖析(三) 关键词：C#,ASPX,ASP,.NET中,分页,自定义发布日期：2015-07-29 12:22
ASP.NET中的分页剖析(二) 关键词：C#,ASPX,ASP,.NET中,分页,自定义发布日期：2015-07-29 12:20
ASP.NET中的分页剖析(五) 关键词：C#,ASPX,ASP,.NET中,分页,自定义发布日期：2015-07-29 12:24

相关目录：.NET，软件开发，ANDROID