ASP.NET MVC 2 学习笔记一: 两个表的连接的信息显示
最近在写一个关于公司内部的请假系统,要用到ASP.NET MVC,于是乎一边学习,一边写代码.下面写写在学习的时候遇到的问题,以及解决办法,留作学习沉淀.
关于模型类的创建就不说了,下面是我用Entity Framework创建的,取名StaffDataModel.edmx,如下图:
上图中有三个表,当做到经理角色时,要显示所有未批准的请假信息,其中所需信息大部分在LeavingInformaion这个表中,但是申请人的英文名字信息在StaffList中,两个表关系是一对多,通过员工Id连接.现在,需要在View视图中显示这些信息,用的是ViewData.Model传的值.这样,仅用ADO.NET Entity Data Model生成的模型类是不够的.
所以,考虑在Models层创建了一个模型类LeavingInfoModel.cs,代码如下:
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Web;
5 using System.Web.Mvc;
6 using System.ComponentModel;
7
8 namespace MvcLeavingApp.Models
9 {
10 /// <summary>
11 /// 请假信息
12 /// </summary>
13 public class LeavingInfoModel
14 {
15 public int infoid;
16 public string enname;
17 public DateTime starttime;
18 public DateTime requesttime;
19 public int relativetime;
20 public DateTime endtime;
21
22 public LeavingInfoModel()
23 {
24 infoid = 0;
25 enname = null;
26 starttime = DateTime.Now;
27 requesttime = DateTime.Now;
28 relativetime = 0;
29 endtime = DateTime.Now;
30 }
31 }
32 }
在LeavingInfoModel这个模型类中,定义了所需要显示的所有字段,并在构造函数中为所有字段赋初值.
那么在Controllers层,对LeavingInformaion和StaffList两个表左连接后,用linq中的Lambda表达式获得符合筛选条件的结果集合,在创建一个对象数组,赋予结果集合,最后传给ViewData.Model.其中 ManagerController.cs的代码如下:
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Web;
5 using System.Web.Mvc;
6 using MvcLeavingApp.Models;
7
8 namespace MvcLeavingApp.Controllers
9 {
10 [HandleError]
11 public class ManagerController : Controller
12 {
13 StaffDataEntities _Staffdb;
14
15 public ManagerController()
16 {
17 _Staffdb = new StaffDataEntities();
18 }
19 /// <summary>
20 /// 查看带审批的请假单
21 /// </summary>
22 /// <returns></returns>
23 public ActionResult ApproveLeave()
24 {
25 var approveInfor = from stafflist in _Staffdb.StaffList
26 from leavinginfo in stafflist.LeavingInformation
27 where leavinginfo.IfApprove == 0
28 select new
29 {
30 infoid = leavinginfo.InfoId,
31 starttime = leavinginfo.StartTime,
32 endtime = leavinginfo.EndTime,
33 relativetime = leavinginfo.RelativeTime,
34 requesttime = leavinginfo.RequestTime,
35 requestname = stafflist.EnName
36 };
37
38 LeavingInfoModel[] leaveinfomodel = new LeavingInfoModel[approveInfor.Count()];
39 int itemindex = 0;
40
41 foreach (var info in approveInfor)
42 {
43 leaveinfomodel[itemindex] = new LeavingInfoModel();
44 leaveinfomodel[itemindex].infoid = info.infoid;
45 leaveinfomodel[itemindex].enname = info.requestname;
46 leaveinfomodel[itemindex].starttime = info.starttime;
47 leaveinfomodel[itemindex].endtime = info.endtime;
48 leaveinfomodel[itemindex].relativetime = info.relativetime;
49 leaveinfomodel[itemindex].requesttime = info.requesttime;
50 itemindex++;
51 }
52
53 ViewData.Model = leaveinfomodel.ToList();
54 return View();
55 }
56 }
可以看到,在ViewData.Model 中已经有了我们所需要的符合条件的结果集.
所以,在View视图中我们可以这样写:
1 <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/SiteManager.Master" Inherits="System.Web.Mvc.ViewPage<List<MvcLeavingApp.Models.LeavingInfoModel>>" %>
2
3 <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
4 ApprovingLeave
5 </asp:Content>
6
7 <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
8 <script src="http://www.cnblogs.com/Scripts/jquery-1.4.1.js" type="text/javascript"></script>
9 <script type="text/javascript">
10 $(function () {
11 $("tr:even").css ({ "background-color": "#CEDBE8" });
12 });
13 </script>
14
15 <h2>Required to Approve Leave</h2>
16 <form method="post" action="/Manager/ApproveLeave">
17 <div>
18 <fieldset>
19 <legend>
20 Require to Approve Absence Form</legend>
21 <table>
22 <thead>
23 <tr>
24 <td align="center">
25 If/Not Approved
26 </td>
27 <td align="center">
28 Start Time
29 </td>
30 <td align="center">
31 End Time
32 </td>
33 <td align="center">
34 Relative Time
35 </td>
36 <td align="center">
37 Request Time
38 </td>
39 <td align="center">
40 Request Staff
41 </td>
42 <td align="center">
43 Details
44 </td>
45 </tr>
46 </thead>
47 <tbody>
48 <% foreach (var m in ViewData.Model)
49 { %>
50 <tr>
51 <td align="center">
52 <%=Html.CheckBox(""+m.infoid) %>
53 </td>
54 <td align="center">
55 <%=m.starttime.ToShortDateString() %>
56 </td>
57 <td align="center">
58 <%=m.endtime.ToShortDateString() %>
59 </td>
60 <td align="center">
61 <%=m.relativetime %>
62 days
63 </td>
64 <td align="center">
65 <%=m.requesttime.ToShortDateString() %>
66 </td>
67 <td align="center">
68 <%=m.enname %>
69 </td>
70 <td align="center">
71 <%= Html.ActionLink("Details", "LeavingDetails", new { infoid = m.infoid })%>
72 </td>
73 </tr>
74 <% } %>
75 </tbody>
76 </table>
77 <p>
78 <input type="submit" value="Approved" />
79 </p>
80 </fieldset>
81 </div>
82 </form>
83 </asp:Content>
其中,页面传值使用System.Web.Mvc.ViewPage<List<MvcLeavingApp.Models.LeavingInfoModel>>来接收,这样我们就可以在ViewData.Model中使用m.enname来得到我们所需要的另一个表中的enname英文名信息了。
这样就可以实现两个表的连接，显示两个表的所有信息了。
Ps：这篇学习笔记同各位分享，并积累一下在ASP.NET MVC 2的学习中所遇到的一系列问题，留作项目沉淀，希望对你有所帮助。第一次写博客，写得不好，还请见谅，如有问题，敬请指出，不胜感激！