groceries/Groceries/Stores/StoreForm.razor

@using Groceries.Data
@using Microsoft.EntityFrameworkCore

@inject IDbContextFactory<AppDbContext> DbContextFactory

<form method="post" @attributes="AdditionalAttributes">
    <div class="form-field">
        <label class="form-field__label" for="storeRetailerId">Retailer</label>
        <select class="form-field__control select" id="storeRetailerId" name="retailerId" required autofocus>
            @foreach (var retailer in retailers)
            {
                <option value="@retailer.Id" selected="@(retailer.Id == Store?.RetailerId)">@retailer.Name</option>
            }
        </select>
    </div>

    <div class="form-field">
        <label class="form-field__label" for="storeName">Name</label>
        <div class="form-field__control input">
            <input class="input__control" id="storeName" name="name" value="@Store?.Name" required />
        </div>
    </div>

    <div class="form-field">
        <label class="form-field__label" for="storeAddress">
            Address <span class="form-field__corner-hint">Optional</span>
        </label>
        <textarea class="form-field__control textarea" id="storeAddress" name="address" rows="4">@Store?.Address</textarea>
    </div>

    @ChildContent
</form>

@code {
    [Parameter]
    public Store? Store { get; set; }

    [Parameter]
    public RenderFragment? ChildContent { get; set; }

    [Parameter(CaptureUnmatchedValues = true)]
    public Dictionary<string, object>? AdditionalAttributes { get; set; }

    private Retailer[] retailers = [];

    protected override async Task OnInitializedAsync()
    {
        using var dbContext = DbContextFactory.CreateDbContext();
        retailers = await dbContext.Retailers
            .OrderBy(retailer => retailer.Name)
            .ToArrayAsync();
    }
}