c# - 使用辅助表列值添加下拉列表
问题描述
我必须在我现有的项目“moviesite”中添加一个,dropdownlist
我有一个电影的主表moviestable
。现在添加了一个新表来添加movieGenre。第二个表由两列组成,“设置为主键和身份,第二列是(包括动作,戏剧,喜剧等类型),并在主表中添加一列并设置为。现在我想访问辅助表主项目中的下拉列。所以我创建了一个新的模型类“ ”并将其添加到。现在我被如何在模型、控制器和索引中实现它所困扰。adding
edit
delete
Genre
GenreId
name
GenreRefId
Foreign-key
GenreClass.cs
dbcontext
NewmovieClass.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.ComponentModel.DataAnnotations;
using Moviesite.Enums;
using System.ComponentModel.DataAnnotations.Schema;
namespace Moviesite.Models
{
public class NewmovieClass
{
[Key]
public int Movieid { get; set; }
[Required]
public string Movietitle { get; set; }
[Required]
public string Description { get; set; }
[Required]
public string Storyline { get; set; }
public int Year { get; set; }
public DateTime Releasedate { get; set; }
public int Runtime { get; set; }
[Column(TypeName="nvarchar(50)")]
public Mvetypenum MovieType { get; set; }
public int GenreRefId { get; set; }
[ForeignKey("GenreRefId")]
public GenreClass Genre { get; set; }
}
}
GenreClass.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.ComponentModel.DataAnnotations;
using Moviesite.Enums;
using System.ComponentModel.DataAnnotations.Schema;
namespace Moviesite.Models
{
public class GenreClass
{
[Key]
public int GenreId { get; set; }
public string Name { get; set; }
public ICollection<NewmovieClass> newmovieClasses { get; set; }
}
}
MveController.cs
using Microsoft.AspNetCore.Mvc;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Moviesite.Models;
using Microsoft.EntityFrameworkCore;
namespace Moviesite.Controllers
{
public class MveController : Controller
{
private readonly ApplicationDbContext _db;
public MveController(ApplicationDbContext db)
{
_db = db;
}
public IActionResult Index()
{
var displaydata = _db.Moviestable.ToList();
return View(displaydata);
}
[HttpGet]
public async Task<IActionResult> Index (String Mvesearch)
{
ViewData["Getmoviedetails"] = Mvesearch;
var mvequery = from x in _db.Moviestable select x;
if (!string.IsNullOrEmpty(Mvesearch))
{
mvequery = mvequery.Where(x => x.Movietitle.Contains(Mvesearch) || x.Description.Contains(Mvesearch));
}
return View(await mvequery.AsNoTracking().ToListAsync());
}
public IActionResult Create()
{
return View();
}
[HttpPost]
public async Task<IActionResult> Create([Bind("Movieid,Movietitle,Description,Storyline,Year,Releasedate,Runtime,MovieType")] NewmovieClass nmc)
{
if (ModelState.IsValid)
{
_db.Add(nmc);
await _db.SaveChangesAsync();
return RedirectToAction("Index");
}
return View(nmc);
}
public async Task< IActionResult> Edit(int? id)
{
if(id==null)
{
return RedirectToAction("Index");
}
var getmvedetails = await _db.Moviestable.FindAsync(id);
return View(getmvedetails);
}
[HttpPost]
public async Task<IActionResult> Edit(NewmovieClass mc)
{
if (ModelState.IsValid)
{
_db.Update(mc);
await _db.SaveChangesAsync();
return RedirectToAction("Index");
}
return View(mc);
}
public async Task<IActionResult> Details(int? id)
{
if (id == null)
{
return RedirectToAction("Index");
}
var getmvedetails = await _db.Moviestable.FindAsync(id);
return View(getmvedetails);
}
public async Task<IActionResult> Delete(int? id)
{
if (id == null)
{
return RedirectToAction("Index");
}
var getmvedetails = await _db.Moviestable.FindAsync(id);
return View(getmvedetails);
}
[HttpPost]
public async Task<IActionResult> Delete(int id)
{
var getmvedetails = await _db.Moviestable.FindAsync(id);
_db.Moviestable.Remove(getmvedetails);
await _db.SaveChangesAsync();
return RedirectToAction("Index");
}
}
}
AppDbcontext
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
namespace Moviesite.Models
{
public class ApplicationDbContext : DbContext
{
public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options) : base(options)
{
}
public DbSet<NewmovieClass> Moviestable { get; set; }
public DbSet<GenreClass> Genre { get; set; }
}
}
解决方案
第一步 fetch 和 List of Genres 并设置在一个viewbag
public IActionResult Create()
{
viewbag.Genres=new SelectList(_db.Genre,"Name","GenreId");
return View();
}
第二步:绑定到dropdown html
<select asp-for="GenreRefId" asp-items="viewbag.Genres"></select>
第三步:添加GenreRefId
MethodePost
[HttpPost]
public async Task<IActionResult> Create([Bind("Movieid,Movietitle,Description,Storyline,Year,Releasedate,Runtime,MovieType,GenreRefId")] NewmovieClass nmc)
{
if (ModelState.IsValid)
{
_db.Add(nmc);
await _db.SaveChangesAsync();
return RedirectToAction("Index");
}
return View(nmc);
}
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