Blazor ASP.NET Core 7.0

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Pages

Pages/Items.razor
@page "/items"          @* url *@
@page "/item/{id:int}"  @* url avec un parameter *@

@if (Items == null)  @* attendre que la valeur soit chargée *@
{
    <p><em>Loading...</em></p>
}
else
{ /* ... */ }
Pages/Items.razor.cs
public partial class Table : ComponentBase
{
    [Parameter]
    public int Id { get; set; }

Form

EditItem.razor
@page "/edititem/{ItemId:int}"

<EditForm Model="@item"
          OnValidSubmit="@HandleValidSubmitAsync"
          OnInvalidSubmit="@HandleInvalidSubmitAsync">

    <button type="submit">Save</button> 
    <button @onclick="Cancel">Cancel</button>           
</EditForm>
EditItem.razor.cs
[Parameter]
public int ItemId { get; set; }

[Inject]
private IItemService ItemService { get; set; }

private Item item = null;

protected override async Task OnInitializedAsync()
{
    item = await ItemDataService.GetItemAsync(ItemId);
}

// when the submit button is clicked and the model is valid
private async Task HandleValidSubmitAsync()
{
    await ItemService.UpdateItemAsync(item);
}

// when the submit button is clicked and the model is not valid
private async Task HandleInvalidSubmitAsync() { }

Input Text

Razor.svg
<div class="form-group row">

    <label for="name"
           class="col-sm-3">
        Item: 
    </label>

    <InputText id="name"
               @bind-Value="Item.Name"
               class="form-control col-sm-8"
               placeholder="Enter name">
    </InputText>
</div>

Entity Framework Core

Using a DbContext factory

DbContext isn't thread safe and isn't designed for concurrent use.
To handle multi-threads scenarios, use a AddDbContextFactory to create a DbContext for each query.

Program.cs
builder.Services.AddDbContextFactory<MyDbContext>();
MyRepository.cs
private readonly IDbContextFactory<MyDbContext> contextFactory;

public DataSummaryRepository(IDbContextFactory<MyDbContext> contextFactory)
{
    this.contextFactory = contextFactory;
}

public async Task<Data> FetchDataAsync()
{
    // create a DbContext for this query, then dispose it once the query has been executed
    using var context = contextFactory.CreateDbContext();
}