Entity FrameWork 实现分页

SQl语句进行分页

SQL语句进行分页主要是应用Entity FrameWork的SqlQuery()传入SQL语句进行查询时分页。

效果展示。



页面代码展示，显示是用Repeater控件进行动态显示

<%@ Page Title="" Language="C#" MasterPageFile="~/HoTai/HoTaiGuanLi.Master" AutoEventWireup="true" CodeBehind="HoTaiYingYYM.aspx.cs" Inherits="OLMS.HoTai.HoTaiYingYYM" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
    <link href="../Assets/css/input.css" rel="stylesheet" />
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.4.1/dist/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
    <div class="pure-form">
        <fieldset>
            <legend>后台管理<i class="fa fa-angle-double-right"></i>类型管理
            <asp:Button ID="Button1" CssClass="   pure-button pure-button-primary tools-button" runat="server" Text="添加音乐类型" OnClick="Button1_Click" />
            </legend>
        </fieldset>
    </div>
    <div>

        <table class="table table-striped">
            <thead>
                <tr>
                    <th scope="col">编号</th>
                    <th scope="col">应用名称</th>
                    <th scope="col">类型名称</th>
                    <th scope="col">歌手名称</th>
                    <th scope="col">歌手价格</th>
                    <th scope="col">操作</th>
                </tr>
            </thead>
            <tbody>
                <asp:Repeater ID="Repeater1" runat="server" OnItemCommand="Repeater1_ItemCommand">
                    <ItemTemplate>

                        <tr>
                            <th scope="row"><%# Eval("AlbumId") %></th> //表的id
                            <td><%# Eval("Title") %></td>
                            <td><%# Eval("Genres.Name") %></td>
                            <td><%# Eval("Artists.Name") %></td>
                            <td><%# Eval("Price") %></td>
                            <td>
                                <asp:LinkButton ID="LinkButton1" CssClass="btn btn-primary" CommandArgument='<%# Eval("AlbumId") %>' CommandName="dianjia" runat="server">编辑</asp:LinkButton>
                                <asp:LinkButton ID="LinkButton2" CssClass="btn btn-light" CommandArgument='<%# Eval("AlbumId") %>' CommandName="delete" runat="server">删除</asp:LinkButton></td>
                        </tr>

                    </ItemTemplate>
                </asp:Repeater>
            </tbody>
        </table>
    </div>
    <div>
        <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
        <asp:Button ID="Button2" runat="server" Text="首页" OnClick="Button2_Click" />
        <asp:Button ID="Button3" runat="server" Text="上一页" OnClick="Button3_Click" />
        <asp:Button ID="Button4" runat="server" Text="下一页" OnClick="Button4_Click" />
        <asp:Button ID="Button5" runat="server" Text="末页" OnClick="Button5_Click" />
    </div>
</asp:Content>

后台事件代码

using OLMS.DAL;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace OLMS.HoTai
{
    public partial class HoTaiYingYYM : System.Web.UI.Page
    {
        static int x = 0;
        static int i = 1;
        static int zyes;
        static int ztian;
        static int tianos = 5;
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                //刷新
                Select();
            }

        }

        private void Select()
        {
            using (OLMSDBEntities db = new OLMSDBEntities())
            {
                string sql = $"select * from Albums order by AlbumId offset {x} rows fetch next 5 rows only";
                Repeater1.DataSource = db.Albums.SqlQuery(sql).ToList();
                Repeater1.DataBind();
                var fy = db.Albums.ToList();
                ztian = fy.Count;
                zyes = ztian / tianos;
                Label1.Text = $"每页5条/共{ztian}条 第{i}页/共{zyes + 1}页";
            }
        }
        protected void Button2_Click(object sender, EventArgs e)
        {
         	//首页
            x = 0;
            i = 1;
            Select();
        }

        protected void Button4_Click(object sender, EventArgs e)
        {
        	//下一页
            x += 5;
            i++;
            if (i >= zyes)
            {
                x = zyes * 5;
                i = zyes + 1;
            }
            if (i >= (zyes + 1))
            {

                string strUrl = "<script>alert('已到末页');</script>";
                Response.Write(strUrl);
            }
            else
            {

                Select();
            }
        }

        protected void Button3_Click(object sender, EventArgs e)
        {
        	//上一页
            x -= 5;
            i--;
            if (x < 0)
            {
                x = 0;
                i = 1;
            }
            if (x <= 0)
            {

                string strUrl = "<script>alert('已到第一页');</script>";
                Response.Write(strUrl);
            }
            else
            {

                Select();
            }

        }

        protected void Button5_Click(object sender, EventArgs e)
        {
        	//末页
            x = zyes * 5;
            i = zyes + 1;
            Select();

        }
    }
}

Skip().Take()进行分页

Skip().Take()进行分页是应用Entity FrameWork的Skip(起始行).Take(每页多少行)方法来进行分页



页面结构和上面是一样的，后台事件代码有区别

using OLMS.DAL;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace OLMS.HoTai
{
    public partial class HoTaiYingYYM : System.Web.UI.Page
    {

        static int i = 1; //起始页数
        static int zyes; //总条数
        static int ztian;//总页数
        static int tianos = 5; //每页多少条
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                //刷新
                Select();
            }

        }

        private void Select()
        {
            using (OLMSDBEntities db = new OLMSDBEntities())
            {

                var fy = db.Albums.ToList();
                ztian = fy.Count;
                zyes = ztian / tianos;
               												    //起始行数        每页多少条
                Repeater1.DataSource = db.Albums.ToList().Skip((i - 1) * tianos).Take(tianos).ToList();
                Repeater1.DataBind();
                Label1.Text = $"每页{tianos}条/共{fy.Count}条 第{i}页/共{(fy.Count / 5) + 1}页";

            }
        }

        protected void Button2_Click(object sender, EventArgs e)
        {

            i = 1;
            Select();
        }

        protected void Button4_Click(object sender, EventArgs e)
        {

            i++;
            if (i >= zyes)
            {
                i = zyes + 1;
            }
            if (i >= (zyes + 1))
            {
                string strUrl = "<script>alert('已到末页');</script>";
                Response.Write(strUrl);
            }
            else
            {

                Select();
            }

        }

        protected void Button3_Click(object sender, EventArgs e)
        {

            i--;
            if (i < 0)
            {
                i = 1;
            }
            if (i <= 0)
            {
                string strUrl = "<script>alert('已到第一页');</script>";
                Response.Write(strUrl);

            }
            else
            {

                Select();
            }

        }

        protected void Button5_Click(object sender, EventArgs e)
        {
            i = zyes + 1;
            Select();
        }
    }
}

总结

Skip().Take()进行分页方法和SQl语句进行分页总体代码差不太多，按具体需要来进行选择。