如何使用Postgresql將值添加到2個表，然后將外鍵從一個表映射到Entity Framework Core中的另一個表？

Question

這是我在ASP.NET Core中遇到的另一個問題，可以說我有2個表：

Accommodation
( ID, Name, LocationID)
Location
(ID, Address, Latitude, Longitude)

我有一個表格：

Name:
Address:
Latitude:
Longitude:

然后，當單擊一個按鈕時，我要在兩個表上同時更新該值，還要將LocationID映射到Accommodation表中。如何在EF Core中對其進行編碼？ 像正確的方法

Answer 1

您可以嘗試下面的示例：

住宿模型和位置模型

 public class Accommodations
{
    public int ID { get; set; }
    public string Name { get; set; }
    public int LocationID { get; set; }
    [ForeignKey("LocationID")]
    public Location Location { get; set; }
}
public class Location
{
    public int ID { get; set; }
    public string Address { get; set; }
    //other stuff you want
}

DbSet在DbContext中的兩個模型

 public class MVCDbContext:DbContext
{
    public MVCDbContext(DbContextOptions<MVCDbContext> options) : base(options)
    { }
    public DbSet<Accommodations> Accommodations { get; set; }
    public DbSet<Location> Location { get; set; }
}

視圖的設計，請注意輸入標簽的asp-for

@model MVC2_1Test.Models.Accommodation.Accommodations
@{
ViewData["Title"] = "Accommondation";
}

<h2>Accommondation</h2>

<div class="row">
<div class="col-md-4">
    <form id="form" class=".has-error" asp-action="CreateAccommodation">
        <div asp-validation-summary="ModelOnly" class="text-danger"></div>
        <div class="form-group ">
            <label asp-for="Name" class="control-label"></label>
            <input asp-for="Name" class="form-control" id="cusName" />
            <span asp-validation-for="Name" class="text-danger"></span>
        </div>
        <div class="form-group">
            <label asp-for="Location.Address" class="control-label"></label>
            <input asp-for="Location.Address" class="form-control" id="age" />
            <span asp-validation-for="Location.Address" class="text-danger"></span>
        </div>
        <div class="form-group">
            <input type="submit" value="Create" class="btn btn-default" />

        </div>
    </form>
</div>
</div>

更新兩個表的動作

[HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> CreateAccommodation([FromForm]Accommodations accommodation)
    {
        if (ModelState.IsValid)
        {
            _context.Add(accommodation);
            await _context.SaveChangesAsync();
            return RedirectToAction(nameof(Index));
        }
        return View(accommodation);
    }