Lookup服务：使用 .Result 异步方法获取值，会导致死锁问题。

[SmartCode-X]

Is there an existing issue for this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe the problem.

public class LookupServiceBaseEntity(ISysUserService sysUserService) : LookupServiceBase
{
private ISysUserService SysUserService { get; } = sysUserService;

public override IEnumerable<SelectedItem>? GetItemsByKey(string? key, object? data)
{
    IEnumerable<SelectedItem>? items = null;
    if (key == "Foo.Complete")
    {
        var users = SysUserService.GetAllUsersAsync().Result;
        //var localizer = Provider.GetRequiredService<IStringLocalizer<Foo>>();//多语言支持
        items = users.Select(user => new SelectedItem
        { Value = user.Id.ToString(), Text = user.Name }).ToList();

    }
    return items;
}

}

Describe the solution you'd like

可以 使用 .Result 异步方法获取值。

Additional context

No response

[bb-auto[bot]]

@SmartCode-X Thank you for reporting. We will give triage later.

[BrandonStudio]

.Result是同步方法啊，阻塞不是正常现象吗

[ArgoZhang]

@SmartCode-X @BrandonStudio Blazor 的世界里可以说有两条定理

async void

.Result

大概率都会遇到问题。各种各样的问题。

[BrandonStudio]

@SmartCode-X 请尝试以下解决方案：

1. 使用 Task.Run

   var users = Task.Run(async () => await SysUserService.GetAllUsersAsync()).GetAwaiter().GetResult();

2. 把 GetAllUsersAsync 中的所有异步调用等待都改成 continueOnCapturedContext: false
   例如

   - var x = await FooAsync(param1);
   + var x = await FooAsync(param1).ConfigureAwait(false);

   参见 https://devblogs.microsoft.com/dotnet/configureawait-faq

[ArgoZhang]

@SmartCode-X @BrandonStudio 昨晚发布了 9.1.3-beta02 支持了异步 Lookup 尽快使用新方法 GetItemsByKeyAsync。帮忙测试一下下

[densen2014]

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