c# - Task.WhenAll 的问题 我如何知道每项任务是否已完成？

Question

如果 TasksList 中的所有任务都成功完成，我只想设置 AllMethodsCompleted = true。但是当我想知道是否一切都已成功完成时，我收到一条错误消息。我做错了什么？

Error CS0029: Cannot implicitly convert type 'void' to 'System.Threading.Tasks.Task'

public async Task PlayerAccountDetails()
{
    var playerCountryData = GetPlayerCountryData();
    var playerTagsData = GetPlayerTagsData();
    var TasksList = new List<Task> { playerCountryData, playerTagsData };

    Task t = await Task.WhenAll(TasksList);
    if (t.Status == TaskStatus.RanToCompletion)
        AllMethodsCompleted = true;
    else
        AllMethodsCompleted = false;
}

Answer 1

Task.WhenAll 将返回一个任务，您可以等待所有任务完成，因此您只需要说:

public async Task PlayerAccountDetails()
{
    var playerCountryData = GetPlayerCountryData();
    var playerTagsData = GetPlayerTagsData();
    var TasksList = new List<Task> { playerCountryData, playerTagsData };

    await Task.WhenAll(TasksList);
    AllMethodsCompleted = true;
}

如果任何任务被取消或抛出异常，则 await Task.WhenAll(TasksList) 行将抛出异常。

如果你想处理其中一项任务的失败，那么你可以这样做:

try
{
    await Task.WhenAll(TasksList);
    AllMethodsCompleted = true;
}
catch
{
    AllMethodsCompleted = false;
}