Webform--LinQ 分页组合查询

来源：互联网发布：mmd动作数据怎么导入编辑：程序博客网时间：2024/04/28 12:59

一、linq高级查

1.模糊查（字符串包含）

  public List<User> Select(string name)     {         return con.User.Where(r =>r.UserName.Contains(name)).ToList();     }

2.查开头（StartsWith,以XX开头）

 public List<User> Select(string name)    {        return con.User.Where(r => r.UserName.StartsWith(name)).ToList();    }

3.查结尾

 public List<User> Select(string name) {        return con.User.Where(r => r.UserName.EndsWith(name)).ToList();    }

4.查出来的数组长度（个数）

clist.Count()

5.最大值：Max(r => r.price);

 public decimal? SelectMax()    {        return con.car.Max(r => r.price);    }

6.最小值：Min(r => r.price);

public decimal? SelectMin()    {        return con.car.Min(r => r.price);    }

7.平均值：Average(r => r.price);

public decimal? SelectAvg()    {        return con.car.Average(r => r.price);    }

8.求和：Sum(r => r.price);

public decimal? SelectSum() { return con.car.Sum(r => r.price); }

9.排序：

1、OrderBy 按升序对值进行排序。
2、OrderByDescending 按降序对值进行排序
3、ThenBy 按升序执行次要排序。
4、ThenByDescending 按降序执行次要排序。
（1）升序：OrderBy(r => r.price)

   public List<car> orderBy()     {         return con.car.OrderBy(r => r.price).ToList();     }

（2）降序：OrderByDescending(r => r.price)

  public List<car> orderBy()    {              return con.car.OrderByDescending(r => r.oil).ToList();    }

10.

ListResult = ListA.Distinct().ToList();//去重
ListResult = ListA.Except(ListB).ToList();//差集
ListResult= ListA.Union(ListB).ToList(); //并集
ListResult = ListA.Intersect(ListB).ToList();//交集

二、分页与组合查询

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml"><head runat="server">    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />    <title></title>    <style>        .image {            width: 30px;            height: 30px;            position: relative;            float: left;            margin-top: 5px;        }        .caozuo {            position: relative;            float: left;            margin-left: 50px;            margin-top: 12px;            width: 50px;            height: 30px;                    }    </style></head><body>    <form id="form1" runat="server">        <div>            昵称：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>            性别：<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>            年龄：<select id="DropDownList1" runat="server">                <option>>=</option>                <option><</option>            </select>            <asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>            <asp:Button ID="Button1" runat="server" Text="查询" /><br />            <br />            <asp:Repeater ID="Repeater1" runat="server">                <HeaderTemplate>                    <table style="width: 100%; text-align: center; background-image: url(images/2.jpg);">                        <tr style="color: red; height: 45px; font-size: 24px;">                            <td>编号</td>                            <td>用户名</td>                            <td>密码</td>                            <td>昵称</td>                            <td>性别</td>                            <td>生日</td>                            <td>民族</td>                            <td>班级</td>                            <td style="text-align: left; width: 180px;">                                <div class="caozuo">操作</div>                                <div class="image">                                    <a href="Insert.aspx" target="_blank">                                        <img src="images/4.png" height="30" width="30" /></a>                                </div>                            </td>                </HeaderTemplate>                <ItemTemplate>                    <tr class="t" style="background-color: white;">                        <td><%#Eval("ids") %></td>                        <td><%#Eval("UserName") %></td>                        <td><%#Eval("PassWord") %></td>                        <td><%#Eval("NickName") %></td>                        <td>                            <img src="<%#Eval("SexStr") %>" />                        </td>                        <td><%#Eval("Birthday","{0:yyyy年MM月dd日}") %></td>                        <td><%#Eval("NationName") %></td>                        <td><%#Eval("ClassName") %></td>                        <td>                            <a href="Delete.aspx?i=<%#Eval("UserName") %>">删除</a>                            <a href="Update.aspx?i=<%#Eval("UserName") %>">修改</a>                        </td>                    </tr>                </ItemTemplate>                <FooterTemplate>                    </table>                </FooterTemplate>            </asp:Repeater>            <div style="width: 800px; height: 20px; margin: auto">                当前第【<asp:Label ID="Label" runat="server" Text="Label"></asp:Label>】页            &nbsp;&nbsp;共【<asp:Label ID="Labe2" runat="server" Text="Label"></asp:Label>】页&nbsp;&nbsp;                        <asp:LinkButton ID="btn_prev" runat="server" CssClass="wenzi">上一页</asp:LinkButton>                &nbsp;&nbsp;            <asp:LinkButton ID="btn_next" runat="server" CssClass="wenzi">下一页</asp:LinkButton>                &nbsp;&nbsp;              </div>        </div>    </form></body></html><script>    var ts = document.getElementsByClassName("t");        for (var i = 0; i < ts.length; i++) {        ts[i].onmouseover = function () {            if (this.style.backgroundColor == "white")                this.style.backgroundColor = "yellow";        };        ts[i].onmouseout = function () {            if (this.style.backgroundColor == "yellow") {                this.style.backgroundColor = "white";            }        };        ts[i].onclick = function () {            for (var j = 0; j < ts.length; j++) {                ts[j].style.backgroundColor = "white";            }                                    var colorArr = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F"];            var colorVal = "#";            for (i = 0; i < 6; i++) {                colorVal += colorArr[Math.round(15 * Math.random())];            }            alert(colorVal)            this.style.backgroundColor= colorVal;        };    }</script>

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;public partial class _Default : System.Web.UI.Page{    int number = 1;   int count=5;    protected void Page_Load(object sender, EventArgs e)    {        if (!IsPostBack)        {            Label.Text = "1";            using (Data0928DataContext con = new Data0928DataContext())            {                double zong=Math.Ceiling(con.Users.ToList().Count/(count*1.0));                Labe2.Text=zong.ToString();               Repeater1.DataSource= con.Users.Skip(count * (number - 1)).Take(count).ToList();                Repeater1.DataBind();            }        }        Button1.Click += Button1_Click;        btn_next.Click += btn_next_Click;        btn_prev.Click += btn_prev_Click;    }    //上一页    void btn_prev_Click(object sender, EventArgs e)    {        int nu = Convert.ToInt32(Label.Text) - 1;        Label.Text = nu.ToString();        if (nu < 1)        {            nu = 1;            Label.Text = "1";            return;}        chaxun();    }    //下一页    void btn_next_Click(object sender, EventArgs e)    {        int nu = Convert.ToInt32(Label.Text) + 1;        Label.Text = nu.ToString();        if (nu > Convert.ToInt32(Labe2.Text))        {            nu = Convert.ToInt32(Labe2.Text.Trim());            Label.Text = Labe2.Text.Trim();            return;        }        chaxun();    }    //查询    void Button1_Click(object sender, EventArgs e)    {        chaxun();    }    //查询方法    private void chaxun()    {        using (Data0928DataContext con = new Data0928DataContext())        {            var All = con.Users.AsQueryable();//AsEnumerale也是一个集合，不会占用系统空间，相当于只是把查询字符串给拼接起来，准备好，当执行ToList时才会进行查询            if (TextBox1.Text.Trim().Length > 0)//说明这里填写了内容            {                var namelist = con.Users.Where(r => r.NickName.Contains(TextBox1.Text.Trim()));                All = All.Intersect(namelist);            }            if (TextBox2.Text.Trim() == "男" || TextBox2.Text.Trim() == "女")            {                var sexlist = con.Users.Where(r => Convert.ToBoolean(r.Sex) == (TextBox2.Text.Trim() == "男" ? true : false));                All = All.Intersect(sexlist);            }            if (TextBox3.Text.Trim().Length > 0)            {                int nowyear = DateTime.Now.Year;                try                {                    int age = Convert.ToInt32(TextBox3.Text.Trim());                    int g = nowyear - age;                    DateTime d = Convert.ToDateTime(g.ToString() + "-1-1");                    if (DropDownList1.SelectedIndex == 1)                    {                        var agelist = con.Users.Where(r => Convert.ToDateTime(r.Birthday) >= d);                        All = All.Intersect(agelist);                    }                    else                    {                        DateTime dd = Convert.ToDateTime(g.ToString() + "-12-31");                        var agelist = con.Users.Where(r => Convert.ToDateTime(r.Birthday) <= dd);                        All = All.Intersect(agelist);                    }                }                catch                {                }            }            double zong = Math.Ceiling(All.ToList().Count / (count * 1.0));//取上限            Labe2.Text = zong.ToString();            Repeater1.DataSource = All.Skip((Convert.ToInt32(Label.Text.Trim())-1)*count).Take(count);            Repeater1.DataBind();        }    }}

阅读全文

0 0