asp.net 分页控件

浏览数：26 / 时间：2015年06月09日

好久不用webform了，这次做的项目又要使用webform(微软推荐使用的是mvc)，闲着没事儿干了的时候写个分页控件出来，废话不多说直接上代码

[
        DefaultEvent("Paging"),
        DefaultProperty("Text"),
        AspNetHostingPermission(SecurityAction.Demand,
            Level = AspNetHostingPermissionLevel.Minimal),
        AspNetHostingPermission(SecurityAction.InheritanceDemand,
            Level = AspNetHostingPermissionLevel.Minimal),
        ToolboxData("<{0}:Pager runat=\"server\"></{0}:Pager>")
    ]
    public class Pager : CompositeControl
    {
        private LinkButton _lbtnPrevious;
        private LinkButton _lbtnNext;
        private DropDownList _ddlPageItem;

        private static readonly object EventPagingKey =
            new object();

        [Bindable(true)]
        [Category("Appearance")]
        [DefaultValue("")]
        [Localizable(true)]
        public string Text
        {
            get
            {
                string s = (string) ViewState["Text"];
                return (s ?? string.Empty);
            }

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

        [Category("Appearance")]
        [DefaultValue(10)]
        [Localizable(true)]
        public int PageSize
        {
            get
            {
                string s = (string) ViewState["PageSize"];
                int pageSize = 0;
                int.TryParse(s, out pageSize);
                return pageSize;
            }
            set { ViewState["PageSize"] = value.ToString(); }
        }

        [Category("Appearance")]
        [DefaultValue(1)]
        [Localizable(true)]
        public int CurrentPageIndex
        {
            get
            {
                string s = (string) ViewState["CurrentPageIndex"];
                int currentPageIndex = 0;
                int.TryParse(s, out currentPageIndex);
                if (currentPageIndex < 1)
                    currentPageIndex = 1;
                return currentPageIndex;
            }
            set { ViewState["CurrentPageIndex"] = value.ToString(); }
        }

        [Category("Appearance")]
        [DefaultValue(0)]
        [Localizable(true)]
        public int RecordCount
        {
            get
            {
                string s = (string) ViewState["RecordCount"];
                int recordCount = 0;
                int.TryParse(s, out recordCount);
                return recordCount;
            }
            set { ViewState["RecordCount"] = value.ToString(); }
        }

        [Category("Appearance")]
        [DefaultValue(0)]
        [Localizable(true)]
        public int PageCount
        {
            get
            {
                string s = (string) ViewState["PageCount"];
                int pageCount = 0;
                int.TryParse(s, out pageCount);
                return pageCount;
            }
            private set { ViewState["PageCount"] = value.ToString(); }
        }

        private void BuildChildControls()
        {
            if (PageSize > 0)
            {
                PageCount = RecordCount / PageSize;
                if (RecordCount % PageSize != 0)
                    PageCount++;
            }

            _lbtnPrevious = new LinkButton { Text = "上一页", ID = "lbtnPrevious", Enabled = (CurrentPageIndex > 1) };
            _lbtnPrevious.Click += _lbtnPrevious_Click;
            this.Controls.Add(_lbtnPrevious);

            _ddlPageItem = new DropDownList { ID = "ddlPageItem", AutoPostBack = true };
            _ddlPageItem.SelectedIndexChanged += _ddlPageItem_SelectedIndexChanged;
            for (var i = 1; i <= PageCount; i++)
            {
                _ddlPageItem.Items.Add(new ListItem(string.Format("第{0}页", i), i.ToString()));
            }
            this.Controls.Add(_ddlPageItem);

            _lbtnNext = new LinkButton { Text = "下一页", ID = "lbtnNext", Enabled = (CurrentPageIndex < PageCount) };
            _lbtnNext.Click += _lbtnNext_Click;
            this.Controls.Add(_lbtnNext);
        }

        protected override void CreateChildControls()
        {
            this.Controls.Clear();
            ClearChildControlState();
            BuildChildControls();
        }

        private void _ddlPageItem_SelectedIndexChanged(object sender, EventArgs e)
        {
            int pageIndex;
            int.TryParse(_ddlPageItem.SelectedItem.Value, out pageIndex);
            CurrentPageIndex = pageIndex;
            OnPaging(e);
        }

        public event EventHandler Paging
        {
            add { this.Events.AddHandler(EventPagingKey, value); }
            remove { this.Events.RemoveHandler(EventPagingKey, value); }
        }

        protected virtual void OnPaging(EventArgs e)
        {
            var submitHandler = (EventHandler) Events[EventPagingKey];
            if (submitHandler != null)
            {
                submitHandler(this, e);
            }

            _lbtnPrevious.Enabled = CurrentPageIndex > 1;
            _lbtnNext.Enabled = CurrentPageIndex < PageCount;

            _ddlPageItem.SelectedValue = CurrentPageIndex.ToString();
        }

        private void _lbtnPrevious_Click(object sender, EventArgs e)
        {
            if (CurrentPageIndex > 1)
            {
                CurrentPageIndex -= 1;
                OnPaging(e);
            }
            else
            {
                _lbtnPrevious.Enabled = false;
            }
        }

        private void _lbtnNext_Click(object sender, EventArgs e)
        {
            if (CurrentPageIndex < PageCount)
            {
                CurrentPageIndex += 1;
                OnPaging(e);
            }
            else
            {
                _lbtnNext.Enabled = false;
            }
        }

        protected override void Render(HtmlTextWriter writer)
        {
            base.Render(writer);
        }
    }