如何在我的网站中加入数据库表？

Question

这是我的代码：

albums.cshtml

@page
@using Project.Models
@model Project.Pages.AlbumsModel
@addTagHelper *, Microsoft.AspNetCore.Mvc.TagHelpers

<div class="row">
    <h1 class="display-2">Albums</h1>
    <table class="table">
        <thead class="thead-inverse">
            <tr>
                <th>Album ID</th>
                <th>Artist ID</th>
                <th>Artist name</th>
                <th>Album title</th>
                <th></th>
                <th></th>
            </tr>
        </thead>

        <tbody>
            @foreach (Album album in Model.Albums)
            {
                <tr>
                    <td>@album.AlbumId</td>
                    <td>@album.ArtistId</td>
                    <td>@Html.DisplayFor(modelArtists => album.Artist.Name)</td>
                    <td>@album.Title</td>
                    <td><a asp-page="/Albums/Details" asp-route-id="@album.AlbumId">Details</a></td>
                    <td><a asp-page="/Albums/Edit" asp-route-id="@album.AlbumId">Edit</a></td>
                    <td><a asp-page="/Albums/Delete" asp-route-id="@album.AlbumId">Delete</a></td>   
                    <td><a asp-page="/Albums/AlbumTracks" asp-route-id="@album.AlbumId">Tracks</a></td>       
                </tr>
            }
        </tbody>
    </table>
</div>
<div class="row">
    <p>Enter a title & ArtistID for a new album:&nbsp;</p>
    <form method="POST">
        <div><input asp-for="Album.Title" /></div>
        <div><input asp-for="Album.ArtistId" /></div>
        <input type="submit" />
    </form>
</div>
<div>
    <a asp-page="/Index">Home</a>
</div>

AlbumTracks.cshtml

@page
@using Project.Models
@model Project.Pages.AlbumTracksModel
@addTagHelper *, Microsoft.AspNetCore.Mvc.TagHelpers

<div class="row">
    <h1 class="display-2">Tracks</h1>
    <table class="table">
        <thead class="thead-inverse">
            <tr>
                <th>Track name</th>
                <th></th>
                <th></th>
                <th></th>
                <th></th>
            </tr>
        </thead>

        <tbody>
            @foreach (Track track in Model.Tracks)
            {
                <tr>
                    <td>@track.TrackId</td>
                    <td>@track.Name</td>
                </tr>
            }
        </tbody>
    </table>
</div>
@* <div class="row">
    <p>Enter a name & TrackID for a new track:&nbsp;</p>
    <form method="POST">
        <div><input asp-for="Track.Name" /></div>
        <div><input asp-for="Track.TrackId" /></div>
        <input type="submit" />
    </form>
</div> *@
<div>
    <a asp-page="/Index">Home</a>
</div>

AlbumTracks.cshtml.cs

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.EntityFrameworkCore;
using Project.Models;
using System;
using System.Collections.Generic;
using System.Linq;

namespace Project.Pages
{
    public class AlbumTracksModel : PageModel
    {
        private Chinook db;

        public AlbumTracksModel(Chinook injectedContext)
        {
            db = injectedContext;
        }
        public IEnumerable<Track> Tracks { get; set; }
        public void OnGetAsync()
        {
            ViewData["Title"] = "Chinook Web Site - Tracks";
            Tracks = db.Tracks.Include(a => a.Album);
        }
    }
}

目前，我正在显示 AlbumTracks.cshtml 中每个专辑中的所有首曲目，而不仅仅是所选的那首由用户在 album.cshtml 上发布。我已经反复阅读 this，但我正在努力找出 AlbumTracks.cshtml 的语法，也许我需要 AlbumTracks.cshtml.cs?

中的更多内容

我想也许我需要使用类似这样的东西来连接表格：

        if (item.AlbumID == Model.AlbumID)

有什么指点吗？ TIA.

编辑：GitHub repo

Answer 1

也许试试：

foreach (var track in Model.Tracks)
{
    if(item.AlbumID == Model.AlbumID)
    {
         <tr>
              <td>@track.TrackId</td>
              <td>@track.Name</td>
         </tr> 
    }
}

你能post你的模特吗？

我的应用程序中有类似的东西，我创建了 2 个模型，例如1 个用于曲目，1 个用于专辑。然后在您的专辑模型中制作一个列表 Tracklist，并在您的曲目模型中制作一个属性 AlbumId。在你的 trackcontroller 中，在创建轨道时你可以有类似

的东西

var albums = _context.Albums.toList // or any other way to retrieve the albums from the DB. 
foreach (var item in albums)
if (track.AlbumId = item.Id)
{
     item.Tracklist.add(Track)
}

我对这个还是有点陌生，所以希望它有用！

Answer 2

At the moment I'm displaying all tracks from every album in AlbumTracks.cshtml, instead of just the one selected by the user on album.cshtml.

你确定你描述的是正确的吗？您可以使用以下代码显示所有专辑中的所有曲目：

Tracks = db.Tracks.Include(a => a.Album);

我想你想要的是点击albums.cshtml中的Trackslink可以显示所选专辑的曲目:

<td><a asp-page="/Albums/Album Tracks" asp-route-id="@album.AlbumId">Tracks</a></td>

如果我说的是正确的，您需要先将 id 参数添加到您的 /Albums/AlbumTracks 方法并修改 linq，如下所示：

public class AlbumTracksModel : PageModel
{
    private Chinook db;

    public AlbumTracksModel(Chinook injectedContext)
    {
        db = injectedContext;
    }
    public IEnumerable<Track> Tracks { get; set; }

    public void OnGetAsync(int id)
    {
        ViewData["Title"] = "Chinook Web Site - Tracks";
        Tracks = db.Tracks.Include(a => a.Album).Where(a=>a.AlbumId==id);
    }
}

AlbumTracks.cshtml:

@page
@using Project.Models
@model Project.Pages.AlbumTracksModel
@addTagHelper *, Microsoft.AspNetCore.Mvc.TagHelpers

<div class="row">
    <h1 class="display-2">Tracks</h1>
    <table class="table">
        <thead class="thead-inverse">
            <tr>
                <th>Track name</th>
                <th></th>
                <th></th>
                <th></th>
                <th></th>
            </tr>
        </thead>

        <tbody>
            @foreach (Track track in Model.Tracks)
            {
                <tr>
                    <td>@track.TrackId</td>
                    <td>@track.Name</td>
                </tr>
            }
        </tbody>
    </table>
</div>

结果：

如何在我的网站中加入数据库表？

How to join database tables in my website?

c#

asp.net

entity-framework

asp.net-core

razor-pages