在Web显示的时候我们经常会遇到分页显示,而网上的分页方法甚多,但都太过于消耗带宽,所以我想到了用Ajax来分页,利用返回的Json来处理返回的数据,

大大简化了带宽的压力。

先说下思路,无非就是异步执行ajax 把新列表所需要的数据用json格式返回来,然后把原来的列表Remove掉,让新列表Show。

上前台Html代码:

<!--一个table 里面是repeater 当然了你也可以用<UL>那样效率更高-->

<table width="100%" border="0" cellpadding="0" id = "newslist" cellspacing="1" bgcolor="b5d6e6">

            <asp:Repeater ID="Repeater1" runat="server">

            <HeaderTemplate>

            <tr>

            <td width="15%" height="22" background="images/bg.gif" bgcolor="#FFFFFF"><div align="center">

             <a id="quan">全选</a>

            <a id="fan">反选</a>

            </div></td> 

             <td width="12%" height="22" background="images/bg.gif" bgcolor="#FFFFFF"><div align="center"><span class="STYLE1">接收号码</span></div></td>

            <td width="14%" height="22" background="images/bg.gif" bgcolor="#FFFFFF"><div align="center"><span class="STYLE1">发送时间</span></div></td>

            <td width="18%" background="images/bg.gif" bgcolor="#FFFFFF"><div align="center"><span class="STYLE1">邮件地址</span></div></td>

            <td width="23%" height="22" background="images/bg.gif" bgcolor="#FFFFFF"><div align="center"><span class="STYLE1">内容</span></div></td>

            <td width="15%" height="22" background="images/bg.gif" bgcolor="#FFFFFF" class="STYLE1"><div align="center">基本操作</div></td>

          </tr>

            </HeaderTemplate>

           <ItemTemplate>

             <tr class="item">

            <td height="20" bgcolor="#FFFFFF"><div align="center">

              <input class ="check_select" type="checkbox" name="checkbox2" title =<%#Eval("Id")%> value="checkbox" />

            </div></td>

            <td height="20" bgcolor="#FFFFFF"><div align="center"><span class="STYLE1"><%#Eval("Name")%></span></div></td>

            <td height="20" bgcolor="#FFFFFF"><div align="center"><span class="STYLE1">2007-11-16 15:00:20 </span></div></td>

            <td bgcolor="#FFFFFF"><div align="center"><span class="STYLE1">tiezhu0902@163.com</span></div></td>

            <td height="20" bgcolor="#FFFFFF"><div align="center"><span class="STYLE1">南京科技股份有限公司…</span></div></td>

            <td height="20" bgcolor="#FFFFFF"><div align="center"><span class="STYLE4"><img src="images/edt.gif" width="16" height="16" />编辑&nbsp; &nbsp;<img src="images/del.gif" width="16" height="16" />删除</span></div></td>

          </tr>

           </ItemTemplate>

            </asp:Repeater>

        </table>

<!--一个table 里面是上一页,下一页,当前页面信息等等……当然了你也可以用<UL>那样效率更高-->

<table width="100%" border="0" cellspacing="0" cellpadding="0">

          <tr>

            <td class="STYLE4"><a id="delete"  style =" cursor :hand;">批量删除</a>

            </td>

             <td class="STYLE4">共有<asp:Label ID="Count" runat="server" Text=""></asp:Label>条数据,

             每页显示<asp:Label ID="ItemCount" runat="server" Text=""></asp:Label>条,

             当前<asp:Label ID="index" runat="server" Text=""></asp:Label>

             /

             <asp:Label ID="PageCount" runat="server" Text=""></asp:Label>

             页

            </td>

            <td><table border="0" align="right" cellpadding="0" cellspacing="0">

                <tr>

                  <td width="40"><img src="images/first.gif" class="page" title ="first" width="37" height="15" /></td>

                  <td width="45"><img src="images/back.gif" class="page" title ="back" width="43" height="15" /></td>

                  <td width="45"><img src="images/next.gif" class="page" title ="next" width="43" height="15" /></td>

                  <td width="40"><img src="images/last.gif" class="page" title ="last" width="37" height="15" /></td>

                  <td width="100"><div align="center"><span class="STYLE1">转到第

                      <asp:DropDownList ID="Drop" runat="server">

                      </asp:DropDownList>                   

                    页 </span></div></td>

                  <td width="40"><img class="page" title = "go" src="images/go.gif" width="37" height="15" /></td>

                </tr>

            </table> 

            </td>

          </tr>

        </table>

好了,初步的html页面布局已经做完了,下来我们该做页面和服务器的交互了

页面引入Jquery,为上一页,下一页,首页,尾页,增加Click事件

利用Linq + Jquery + Ajax 异步分页的实现_数据

设置他们的Class = page 以便于给他们增加Click

 $(".page").click(function () {

                var type = $(this).attr("title");

                var thisindex = $("#index").text(); //获取当前页码

                switch (type) {

                    case 'first':

                        {

                            pageindex = 1;

                            PageIndex(1);  //Ajax 回传函数

                            return;

                        }

                    case 'back':

                        {

                            if (thisindex == 1) {

                                alert("当前已经是第一页!");

                            }

                            else {

                                pageindex = parseInt(thisindex) - 1;

                                PageIndex(pageindex);

                            }

                            return;

                        }

                    case 'next':

                        {

                            if (thisindex == $("#Drop").children().length) {

                                alert("当前已经是最后页!");

                            }

                            else {

                                pageindex = parseInt(thisindex) + 1;

                                PageIndex(pageindex);

                            }

                            return;

                        }

                    case 'last':

                        {

                            var max = $("#Drop").children().length;

                            pageindex = max;

                            PageIndex(max);

                            return;

                        }

                    case 'go':

                        {

                            var _go = $("#Drop").val();

                            pageindex = _go;

                            PageIndex(_go);

                            return;

                        }

                }

            })

下面的代码在是Ajax的回传封装,切记在$(function(){ ....})之外

var pageindex;

        function PageIndex(index) {

            $.ajax({

                type: "Post", //回传格式

                url: "WebForm1.aspx", //回传页面

                data: { "id": index },  //回传参数表示请求的是第几页

                cache: false, //禁止使用浏览器缓存

                //dataType: "json",

                success: function (data) {

                    var json = eval(data); //把返回来的数据 json

                    var str = "";

                    for (var i = 0; i < json.items.length - 1; i++) {

                        str = str + "<tr class='item' ><td height='20' bgcolor='#FFFFFF'><div align='center'><input class ='check_select' type='checkbox' name='checkbox2' title =" + json.items[i].id.toString() + " value='checkbox' /></div></td>";

                        str = str + "<td height='20' bgcolor='#FFFFFF'><div align='center'><span class='STYLE1'>" + json.items[i].name + "</span></div></td><td height='20' bgcolor='#FFFFFF'><div align='center'><span class='STYLE1'>2007-11-16 15:00:20 </span></div></td>";

                        str = str + "<td bgcolor='#FFFFFF'><div align='center'><span class='STYLE1'>tiezhu0902@163.com</span></div></td><td height='20' bgcolor='#FFFFFF'><div align='center'><span class='STYLE1'>南京科技股份有限公司…</span></div></td>";

                        str = str + "<td height='20' bgcolor='#FFFFFF'><div align='center'><span class='STYLE4'><img src='images/edt.gif' width='16' height='16' />编辑&nbsp; &nbsp;<img src='images/del.gif' width='16' height='16' />删除</span></div></td></tr>";

                    }

                    $("#index").text(pageindex); //设置当前的页码

                    $(".item").remove(); //移除原有的列表

                    $("#newslist").append(str); //显示返回的列表

                },

                error: function () {

                    alert("服务错误");

                }

            })

        }

下面才C#代码了:

void data(int id,bool b)

        {

            int listcount = 7; //设置页面的显示数量

            LinqToSqlDataContext ds = new LinqToSqlDataContext();

            var q = (from a in ds.Admin select a).Skip((id-1) * listcount).Take(listcount); //获取请求页面的列表

            if (!b)  //如果是页面初始加载 默认显示

            {

                Repeater1.DataSource = q;

                DataBind();

                int count = (from a in ds.Admin select a).ToList().Count;

                this.Count.Text = count.ToString();                

                count = count / listcount + (count % listcount > 0 ? 1 : 0);

                this.ItemCount.Text = listcount.ToString();

                this.index.Text = "1";

                this.PageCount.Text = count.ToString();

                for (int i = 0; i < count; i++)

                {

                    Drop.Items.Add((i + 1).ToString());

                }

            }

            else

            {

                string str = "({items:[";                

                foreach (var a in q)

                {

                    str += "{'id':'" + a.Id + "'";

                    str += ",'name':'" + a.Name+"'";

                    str += "},";

                }

                str += "]})";

                Response.Write(str);

                Response.End();

            }

        }

        protected void Page_Load(object sender, EventArgs e)

        {

            if (!IsPostBack)

            {

                data(1,false);

            }

            PageIndex();

        }

        void PageIndex()

        {

            if (Request["id"] != null)

            {

                int id = int.Parse(Request["id"].ToString());

                data(id,true);

            }

        }

好了,到此,大功告成,后续会把批量删除(批量删除后的页面变化等等加入),