winform分页管理

注意：其中可能用到部分自定义的扩展方法，在使用中需自己修改一下

    /// <summary>
    /// 分页管理
    /// </summary>
    public class Paging
    {
        #region Property

        private int pageCount;   //总页数
        /// <summary>
        /// 每页数
        /// </summary>
        public int PageSize = 10;
        /// <summary>
        /// 总数
        /// </summary>
        public int Total = 0;
        /// <summary>
        /// 当前页数 
        /// </summary>
        public int PageIndex = 1;

        public int PageCount
        {
            get
            {
                if (PageSize <= 0)
                    PageSize = 1;
                if (Total % PageSize == 0)
                {
                    pageCount = Total / PageSize;
                }
                else
                {
                    pageCount = Total / PageSize + 1;
                }
                return pageCount;
            }
            set
            {
                pageCount = value;
            }

        }
        #endregion

        /// <summary>
        /// 分页操作，name默认为"",否则为操作控件的Name
        /// </summary>
        /// <param name="bn">分页控件菜单</param>
        /// <param name="name">操作类型</param>
        public void SplitMenu(BindingNavigator bn, string name)
        {
            #region Name
            string tstbPageSize = bn.Items[1].Name;
            string tstbPageIndex = bn.Items[7].Name;
            string tslPageCount = bn.Items[8].Name;
            string tsbFirst = bn.Items[4].Name;
            string tsbPageUp = bn.Items[5].Name;
            string tsbPageDown = bn.Items[10].Name;
            string tsbLast = bn.Items[11].Name;
            #endregion

            try
            {
                this.PageSize = bn.Items[tstbPageSize].Text.ToString().ToInt(0);
                this.PageIndex = bn.Items[tstbPageIndex].Text.ToString().ToInt(0);
                #region action
                if (name == tsbFirst)
                    PageIndex = 1;
                else if (name == tsbPageUp)
                    PageIndex--;
                else if (name == tsbPageDown)
                    PageIndex++;
                else if (name == tsbLast)
                    PageIndex = PageCount;
                else if ((name == tstbPageIndex) || (name == tstbPageSize) || (name == "delete"))
                {
                    int index = bn.Items[tstbPageIndex].Text.ToString().ToInt(1);
                    int size = bn.Items[tstbPageSize].Text.ToString().ToInt(1);
                    if (size == 0)
                        size = 1;
                    if (size > Total)
                    {
                        //if (Total != 0)
                        //    size = Total;
                        if (PageIndex * PageSize > Total)
                            PageIndex = 1;
                    }
                    PageSize = size;
                    if (index > PageCount)
                        index = PageCount;
                    PageIndex = index;
                }
                //else
                //{
                //    //bn.Items[tsbFirst].Enabled = false;
                //    //bn.Items[tsbPageUp].Enabled = false;
                //    //bn.Items[tsbLast].Enabled = false;
                //    //bn.Items[tsbPageDown].Enabled = false;
                //}
                #endregion
            }
            catch (Exception ex)
            {
                Fn.ShowWarning(ex.Message);
            }

            #region show
            if (PageIndex <= 1)
            {
                PageIndex = 1;
                bn.Items[tsbFirst].Enabled = false;
                bn.Items[tsbPageUp].Enabled = false;
            }
            else
            {
                bn.Items[tsbFirst].Enabled = true;
                bn.Items[tsbPageUp].Enabled = true;
            }
            if (PageIndex == PageCount)
            {
                bn.Items[tsbLast].Enabled = false;
                bn.Items[tsbPageDown].Enabled = false;
            }
            else
            {
                bn.Items[tsbLast].Enabled = true;
                bn.Items[tsbPageDown].Enabled = true;
            }
            if (Total == 0)
            {
                bn.Items[tsbFirst].Enabled = false;
                bn.Items[tsbPageUp].Enabled = false;
                bn.Items[tsbLast].Enabled = false;
                bn.Items[tsbPageDown].Enabled = false;
            }
            bn.Items[tstbPageSize].Text = PageSize.ToString();
            bn.Items[tstbPageIndex].Text = PageIndex.ToString();
            bn.Items[tslPageCount].Text = "/{" + PageCount.ToString() + "}页";

            #endregion
        }

        /// <summary>
        /// 获取当前页
        /// </summary>
        /// <param name="dt">数据源</param>
        /// <returns></returns>
        public DataTable GetDataTable(DataTable dt)
        {
            DataTable dtTemp = dt.Clone();
            int dtCount = dt.Rows.Count;
            if (dtCount == 0)
            {
                return dtTemp;
            }
            int start = (PageIndex - 1) * PageSize;
            int end = PageIndex * PageSize;
            if (start > dtCount)
                start = 0;
            if (end > dtCount)
                end = dtCount;
            for (int i = start; i < end; i++)
            {
                if (i>dt.Rows .Count )
                {
                    continue;
                }
                DataRow row = dtTemp.NewRow();
                row.ItemArray = dt.Rows[i].ItemArray;
                dtTemp.Rows.Add(row);
            }
            return dtTemp;
        }
    }