WinForm分页控件

分页控件是程序开发的数据加载显示中较常用，为了能够灵活重用，以下使用将该功能包装成用户控件UserControl，整体控件效果图如下：

分页paging完整代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace DiaGramApp
{
   /// <summary>

    /// 声明委托

    /// </summary>

    /// <param name="e"></param>

    public delegate void EventPagingHandler(EventArgs e);

    public partial class Paging : UserControl

    {
        public Paging()

        {
            InitializeComponent();
        }
        public event EventPagingHandler EventPaging;

        #region 公开属性
        private int _pageSize = 20;
        /// <summary>
        /// 每页显示记录数(默认20)
        /// </summary>
        public int PageSize
        {
            get
            {
                return _pageSize;
            }
            set 
            {
                if (value > 0)
                {
                    _pageSize = value;
                    this.comboPageSize.Text = _pageSize.ToString();
                }
               else if (value == -1)
                {
                    _pageSize = -1;
                }
                else
                {
                    _pageSize = 20;
                    this.comboPageSize.Text = _pageSize.ToString();
                }
                
            }
        }

        private int _currentPage = 1;
        /// <summary>
        /// 当前页
        /// </summary>
        public int CurrentPage
        {   
            get 
            {
                return _currentPage;
            }
            set 
            {
                if (value > 0)
                {
                   _currentPage = value;
                }
                else
                {
                    _currentPage = 1;
                }
            }
        }
        private int _totalCount = 0;
        /// <summary>
        /// 总记录数
        /// </summary>
        public int TotalCount
        {
            get
            {
                return _totalCount;
            }
            set 
            {
                if (value>=0)
                {
                    _totalCount = value;
                } 
                else
                {
                    _totalCount = 0;
                }
                this.lblTotalCount.Text = this._totalCount.ToString();

                CalculatePageCount();

                this.lblRecordRegion.Text = GetRecordRegion();
            }
        }
        private int _pageCount = 0;
        /// <summary>
        /// 页数
        /// </summary>
        public int PageCount
        {
            get
            {
                return _pageCount;
            }
            set 
            {
                if (value>=0)
                {
                    _pageCount = value;
                } 
                else
                {
                    _pageCount = 0;
                }
                this.lblPageCount.Text = _pageCount + "";
            }
        }
       #endregion
        /// <summary>
        /// 计算页数
        /// </summary>
        private void CalculatePageCount()
        {
            if (this.TotalCount>0)
            {
                this.PageCount = Convert.ToInt32(Math.Ceiling(Convert.ToDouble(this.TotalCount) / Convert.ToDouble(this.PageSize)));
            }
            else
            {
                this.PageCount = 0;
            }
        }
        /// <summary>
        /// 获取显示记录区间（格式如：1-20）
        /// </summary>
        /// <returns></returns>
        private string GetRecordRegion()
        {
            if (this.PageCount == 1) //只有一页
            {
                return "1-" + this.TotalCount.ToString();
            }
            else  //有多页
            {
                if(this.CurrentPage==1) //当前显示为第一页
                {
                    return "1-"+this.PageSize;
                }
                else if(this.CurrentPage==this.PageCount) //当前显示为最后一页
                {

                    return ((this.CurrentPage-1)*this.PageSize+1) +"-"+this.TotalCount;
                }
                else //中间页
                {
                    return ((this.CurrentPage-1) * this.PageSize+1)   + "-" + this.CurrentPage  * this.PageSize;
                }
            }
        }
        /// <summary>
        /// 数据绑定
        /// </summary>
        public void Bind()
        {
            if (this.EventPaging != null)//当事件不为空时，进行数据绑定
            {
                this.EventPaging(new EventArgs());
            }
            if (this.CurrentPage>this.PageCount)
            {
                this.CurrentPage = this.PageCount;
            }
            this.txtBoxCurPage.Text = this.CurrentPage+"";
            this.lblTotalCount.Text = this.TotalCount+"";
            this.lblPageCount.Text = this.PageCount+"";
            this.lblRecordRegion.Text = GetRecordRegion();
            if (this.CurrentPage==1)
            {
                this.btnFirst.Enabled = false;
                this.btnPrev.Enabled = false;
                //this.btnFirst.Image = global::CHVM.Properties.Resources.page_first_disabled;
                //this.btnPrev.Image = global::CHVM.Properties.Resources.page_prev_disabled;
            }
            else
            {
                this.btnFirst.Enabled = true;
                this.btnPrev.Enabled = true;

            }
            if (this.CurrentPage == this.PageCount)
            {
                this.btnNext.Enabled = false;
                this.btnLast.Enabled = false;
            } 
            else
            {
                this.btnNext.Enabled = true;
                this.btnLast.Enabled = true;
            }
            if (this.TotalCount==0)
            {
                this.btnFirst.Enabled = false;
                this.btnPrev.Enabled = false;
                this.btnNext.Enabled = false;
                this.btnLast.Enabled = false;
            }
        }
        private void btnFirst_Click(object sender, EventArgs e)
        {
            this.CurrentPage = 1;
            this.Bind();
        }
        private void btnPrev_Click(object sender, EventArgs e)
        {
            this.CurrentPage -= 1;            
            this.Bind();
        }
        private void btnNext_Click(object sender, EventArgs e)
        {
            this.CurrentPage += 1;
            this.Bind();
        }
        private void btnLast_Click(object sender, EventArgs e)
        {
            this.CurrentPage = this.PageCount;
            this.Bind();
        }
        /// <summary>
        ///  改变每页条数
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void comboPageSize_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (comboPageSize.Text.Trim() == "全部")
            {
                this.PageSize = -1;//暂时全部时默认为-1
            }
            else
            {
                this.PageSize = Convert.ToInt32(comboPageSize.Text);
            }
            this.Bind();
        } 
   }
}

调用方式：
在调用的窗体中拖入该控件，在InitializeComponent();下加入
this.paging1.EventPaging += new EventPagingHandler(paging1_EventPaging);//初始化自定义事件
然后实现该事件，主要在其中绑定分页数据
        void paging1_EventPaging(EventArgs e)//事件实现
        {

            GvDataBind(); //DataGridView数据绑定   
        }
        private void GvDataBind()
        {

            int SumCount=0;
            DataTable _Dt = new DataTable();
            //获取分页
            if (paging1.PageSize == -1)//为显示全部时的情况
            {

                _Dt = cutlineBLL.GetPaging_BLL(paging1.PageSize, paging1.CurrentPage, out SumCount);
                paging1.PageSize = SumCount;
            }
            else
            _Dt= cutlineBLL.GetPaging_BLL(paging1.PageSize, paging1.CurrentPage, out SumCount);
            dataGridView1.AutoGenerateColumns = false;
            dataGridView1.DataSource = _Dt;
            paging1.TotalCount = SumCount;
            
        }

Load事件中初始化数据并关联分页控件
       GvDataBind();
       paging1.Bind();
本文采用的轻量型数据库sqlite，其分页sql语句如下

/// <summary>
        /// 通用分页查询方法
        /// </summary>
        /// <param name="connString">连接字符串</param>
        /// <param name="tableName">表名</param>
        /// <param name="strColumns">查询字段名</param>
        /// <param name="strWhere">where条件</param>
        /// <param name="strOrder">排序条件</param>
        /// <param name="pageSize">每页数据数量</param>
        /// <param name="currentIndex">当前页数</param>
        /// <param name="recordOut">数据总量</param>
        /// <returns>DataTable数据表</returns>
public static DataTable SelectPaging(string tableName, string strColumns, string strWhere, string strOrder, int pageSize, int currentIndex, out int recordOut)
        {
            DataTable dt = new DataTable();
            recordOut = Convert.ToInt32(ExecuteScalar( "select count(*) from " + tableName));
            string pagingTemplate = "select {0} from {1} where {2} order by {3} limit {4} offset {5} ";
            int offsetCount = (currentIndex - 1) * pageSize;
            string commandText = String.Format(pagingTemplate, strColumns, tableName, strWhere, strOrder, pageSize.ToString(), offsetCount.ToString());
            DataSet ds= ExecuteDataSet(commandText);
            dt = ds.Tables[0];
            return dt;
        }

其中在sqlite中limit为显示的条数，offset为从多少条后开始读取数据。

今天的文章WinForm分页控件分享到此就结束了，感谢您的阅读。