Csharp ASP.NET Core Razor Pages 模型绑定

我对ASP.NET Core Razor页面非常陌生，我希望在以下方面得到您的帮助.

我有以下两节课:

public class Customer
{
    [Key]
    public int Id { get; set; }
    [Required(ErrorMessage ="Please enter a name.")]
    [Display(Name ="Customer Name")]
    public string CustomerName { get; set; }
    [Display(Name = "Customer Email")]
    public string CustomerEmail { get; set; } = string.Empty;
    [Display(Name ="Customer Phone Number")]
    public string CustomerPhoneNumber { get; set; } = string.Empty;

    public List<Invoice> Invoices { get; set; } = new();
}

和

public class Invoice
{
    [Key]
    public int Id { get; set; }
    [Display(Name ="Invoice Number")]
    public string InvNumber { get; set; }
    [Display(Name = "Invoice Amount")]
    public decimal InvAmount { get; set; }
    [Display(Name = "Issued? (Yes/No)")]
    public bool InvIssued { get; set; } = false;
    [Display(Name = "Paid? (Yes/No)")]
    public bool InvPaid { get; set; } = false;

    public int CustomerId { get; set; }
}

The way I've set it up is for a one-to-many relationship. Now, two related issues are that during the Create form for an invoice I also need to input a CustomerId, otherwise I get an SQL exception error. However, for the life of me, I can't figure out how to bind the data, to the Customer table, so that I can retrieve the list of available customers 和 have it as an option during the creation of an invoice.

我的.cshtml文件包含:

       <div class="form-group">
            <label asp-for="Invoice.CustomerId" class="control-label"></label>
            <input asp-for="Invoice.CustomerId" class="form-control" value="3"/>
            <span asp-validation-for="Invoice.InvNumber" class="text-danger"></span>
        </div>

        <div class="form-group">
            <label asp-for="Invoice.InvNumber" class="control-label"></label>
            <input asp-for="Invoice.InvNumber" class="form-control" />
            <span asp-validation-for="Invoice.InvNumber" class="text-danger"></span>
        </div>
        <div class="form-group">
            <label asp-for="Invoice.InvAmount" class="control-label"></label>
            <input asp-for="Invoice.InvAmount" class="form-control" />
            <span asp-validation-for="Invoice.InvAmount" class="text-danger"></span>
        </div>
 
        <div class="form-check">
            <input class="form-check-input" type="radio" name="InvIssued" id="InvIssued" value="true" checked="">
            <label class="form-check-label" asp-for="Invoice.InvIssued">
                The invoice has been issued.
            </label>
        </div>
        <div class="form-check">
            <input class="form-check-input" type="radio" name="InvNotIssed" id="InvNotIssed" value="false">
            <label class="form-check-label" asp-for="Invoice.InvIssued">
                The invoice has not been issued.
            </label>
        </div>
        
        <div class="form-group">
            <input type="submit" value="Create" class="btn btn-primary" />
        </div>
    </form>
</div>

和 my page model is:

public class AddInvoiceModel : PageModel
{
    private readonly InvoicesAppContext InvoiceContext;

    public AddInvoiceModel(InvoicesAppContext contextInvoices)
    {
        InvoiceContext = contextInvoices;
    }

    public IActionResult OnGet()
    {
        return Page();
    }

    [BindProperty]
    public Invoice Invoice { get; set; }


    // To protect from overposting attacks, see https://aka.ms/RazorPagesCRUD
    public async Task<IActionResult> OnPostAsync()
    {
        if (!ModelState.IsValid)
        {
            return Page();
        }

       InvoiceContext.Invoice.Add(Invoice);
       await InvoiceContext.SaveChangesAsync();

       return RedirectToPage("../Index");
    }
}

所以我的问题是:

• 如何在AddInvoice页模型中添加对Customer表的引用？
• The CustomerId is an int 和 not the actual name of the customer. How do I retrieve the names 和 not the id?

感谢你们所有人的帮助.对于这些基本的东西，我很抱歉.我还在学习.