GridView控件（十）——再增加一种分页样式

用着GridView自带的分页样式总觉得不太习惯，我们可以在PagerTemplate中来写一些自定义的样式，但是也挺麻烦的，其实我们可以扩展一下GridView，给它再增加一种分页样式
控件开发
1、新建一个继承自GridView的类。

/**//// <summary>
/// 继承自GridView
/// </summary>
[ToolboxData(@"<{0}:SmartGridView runat='server'></{0}:SmartGridView>")]
public class SmartGridView : GridView
{
}

2、新建一个Paging类，定义一个分页样式的枚举

using System;
using System.Collections.Generic;
using System.Text;

using System.ComponentModel;

namespace YYControls.SmartGridView
{
    /**//// <summary>
    /// 自定义分页相关
    /// </summary>
    public class Paging
    {
        /**//// <summary>
        /// 自定义分页样式
        /// </summary>
        public enum PagingStyleCollection
        {
            /**//// <summary>
            /// 不用自定义分页样式
            /// </summary>
            None,
            /**//// <summary>
            /// 默认自定义分页样式
            /// </summary>
            Default
        }
    }
}

3、在继承自GridView的类中加一个上面定义的枚举属性

        private Paging.PagingStyleCollection _pagingStyle;
        /**//// <summary>
        /// 自定义分页样式
        /// </summary>
        [Description("自定义分页样式"), DefaultValue(""), Category("扩展")]
        public Paging.PagingStyleCollection PagingStyle
        {
            get { return _pagingStyle; }
            set { _pagingStyle = value; }
        }

4、如果GridView使用的是数据源控件的话，计算总记录数

   /**//// <summary>
        /// OnLoad
        /// </summary>
        /// <param name="e"></param>
        protected override void OnLoad(EventArgs e)
        {
            // 查找ObjectDataSource
            ObjectDataSource ods = Parent.FindControl(this.DataSourceID) as ObjectDataSource;
            if (ods != null)
            {
                ods.Selected += new ObjectDataSourceStatusEventHandler(ods_Selected);
            }

            base.OnLoad(e);
        }

        private int? _recordCount = null;
        /**//// <summary>
        /// 计算总记录数
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void ods_Selected(object sender, ObjectDataSourceStatusEventArgs e)
        {
            if (e.ReturnValue is IListSource)
            {
                _recordCount = ((IListSource)e.ReturnValue).GetList().Count;
            }
        }

5、重写OnRowCreated以实现自定义分页样式

      /**//// <summary>
        /// OnRowCreated
        /// </summary>
        /// <param name="e"></param>
        protected override void OnRowCreated(GridViewRowEventArgs e)
        {
            if (e.Row.RowType == DataControlRowType.Pager && PagingStyle == Paging.PagingStyleCollection.Default)
            {
                LinkButton First = new LinkButton();
                LinkButton Prev = new LinkButton();
                LinkButton Next = new LinkButton();
                LinkButton Last = new LinkButton();

                TableCell tc = new TableCell();

                e.Row.Controls.Clear();
                
                tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));
                if (_recordCount.HasValue)
                {
                    tc.Controls.Add(new LiteralControl(_recordCount.ToString()));
                    tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));
                    tc.Controls.Add(new LiteralControl(PageSize.ToString()));
                    tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));
                }
                tc.Controls.Add(new LiteralControl((PageIndex + 1).ToString()));
                tc.Controls.Add(new LiteralControl("/"));
                tc.Controls.Add(new LiteralControl(PageCount.ToString()));
                tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;&nbsp;&nbsp;"));

                if (!String.IsNullOrEmpty(PagerSettings.FirstPageImageUrl))
                {
                    First.Text = "<img src='" + ResolveUrl(PagerSettings.FirstPageImageUrl) + "' border='0'/>";
                }
                else
                {
                    First.Text = PagerSettings.FirstPageText;
                }
                First.CommandName = "Page";
                First.CommandArgument = "First";
                First.Font.Underline = false;

                if (!String.IsNullOrEmpty(PagerSettings.PreviousPageImageUrl))
                {
                    Prev.Text = "<img src='" + ResolveUrl(PagerSettings.PreviousPageImageUrl) + "' border='0'/>";
                }
                else
                {
                    Prev.Text = PagerSettings.PreviousPageText;
                }
                Prev.CommandName = "Page";
                Prev.CommandArgument = "Prev";
                Prev.Font.Underline = false;


                if (!String.IsNullOrEmpty(PagerSettings.NextPageImageUrl))
                {
                    Next.Text = "<img src='" + ResolveUrl(PagerSettings.NextPageImageUrl) + "' border='0'/>";
                }
                else
                {
                    Next.Text = PagerSettings.NextPageText;
                }
                Next.CommandName = "Page";
                Next.CommandArgument = "Next";
                Next.Font.Underline = false;

                if (!String.IsNullOrEmpty(PagerSettings.LastPageImageUrl))
                {
                    Last.Text = "<img src='" + ResolveUrl(PagerSettings.LastPageImageUrl) + "' border='0'/>";
                }
                else
                {
                    Last.Text = PagerSettings.LastPageText;
                }
                Last.CommandName = "Page";
                Last.CommandArgument = "Last";
                Last.Font.Underline = false;

                if (this.PageIndex <= 0)
                {
                    First.Enabled = Prev.Enabled = false;
                }
                else
                {
                    First.Enabled = Prev.Enabled = true;
                }

                tc.Controls.Add(First);
                tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));
                tc.Controls.Add(Prev);
                tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));

                // 当前页左边显示的数字分页按钮的数量
                int rightCount = (int)(PagerSettings.PageButtonCount / 2);
                // 当前页右边显示的数字分页按钮的数量
                int leftCount = PagerSettings.PageButtonCount % 2 == 0 ? rightCount - 1 : rightCount;
                for (int i = 0; i < PageCount; i++)
                {
                    if (PageCount > PagerSettings.PageButtonCount)
                    {
                        if (i < PageIndex - leftCount && PageCount - 1 - i > PagerSettings.PageButtonCount - 1)
                        {
                            continue;
                        }
                        else if (i > PageIndex + rightCount && i > PagerSettings.PageButtonCount - 1)
                        {
                            continue;
                        }
                    }

                    if (i == PageIndex)
                    {
                        tc.Controls.Add(new LiteralControl("<span style='color:red;font-weight:bold'>" + (i + 1).ToString() + "</span>"));
                    }
                    else
                    {
                        LinkButton lb = new LinkButton();
                        lb.Text = (i + 1).ToString();
                        lb.CommandName = "Page";
                        lb.CommandArgument = (i + 1).ToString();

                        tc.Controls.Add(lb);
                    }

                    tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));
                }

                if (this.PageIndex >= PageCount - 1)
                {
                    Next.Enabled = Last.Enabled = false;
                }
                else
                {
                    Next.Enabled = Last.Enabled = true;
                }
                tc.Controls.Add(Next);
                tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));
                tc.Controls.Add(Last);
                tc.Controls.Add(new LiteralControl("&nbsp;&nbsp;"));

                tc.ColumnSpan = this.Columns.Count;
                e.Row.Controls.Add(tc);
            }

            base.OnRowCreated(e);
        }

控件使用
添加这个控件到工具箱里，然后拖拽到webform上，设置PagingStyle属性为Default，同时设置GridView的原有属性PageButtonCount，FirstPageText，PreviousPageText，NextPageText，LastPageText，FirstPageImageUrl，PreviousPageImageUrl，NextPageImageUrl，LastPageImageUrl
ObjData.cs

using System;
using System.Data;
using System.Configuration;
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 System.ComponentModel;

/**//// <summary>
/// OjbData 的摘要说明
/// </summary>
public class OjbData
{
    public OjbData()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }

    [DataObjectMethod(DataObjectMethodType.Select, true)]
    public DataTable Select()
    {
        DataTable dt = new DataTable();
        dt.Columns.Add("no", typeof(string));
        dt.Columns.Add("name", typeof(string));

        for (int i = 0; i < 30; i++)
        {
            DataRow dr = dt.NewRow();
            dr[0] = "no" + i.ToString().PadLeft(2, '0');
            dr[1] = "name" + i.ToString().PadLeft(2, '0');

            dt.Rows.Add(dr);
        }

        return dt;
    }
}

Default.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>SmartGridView测试</title>
</head>
<body>
    <form id="form1" runat="server">
        <div>
            <yyc:SmartGridView ID="SmartGridView1" runat="server" DataSourceID="ObjectDataSource1"
                AutoGenerateColumns="False" AllowPaging="true" PagingStyle="Default">
                <Columns>
                    <asp:BoundField DataField="no" HeaderText="序号" SortExpression="no" ItemStyle-Width="100px" />
                    <asp:BoundField DataField="name" HeaderText="名称" SortExpression="name" ItemStyle-Width="100px" />
                    <asp:BoundField DataField="no" HeaderText="序号" SortExpression="no" ItemStyle-Width="100px" />
                    <asp:BoundField DataField="name" HeaderText="名称" SortExpression="name" ItemStyle-Width="100px" />
                    <asp:BoundField DataField="no" HeaderText="序号" SortExpression="no" ItemStyle-Width="100px" />
                    <asp:BoundField DataField="name" HeaderText="名称" SortExpression="name" ItemStyle-Width="100px" />
                </Columns>
            </yyc:SmartGridView>
            <asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="Select"
                TypeName="OjbData"></asp:ObjectDataSource>
        </div>
    </form>
</body>
</html>