Windows窗体无法执行多个异步任务

Question

请纠正我做错的地方。代码如下：

public partial class Form1 : Form
{
   private async void button1_Click(object sender, EventArgs e)
   {
      var itemList = new List<string>() { "Field1", "Field2", "Field3" };

      await Task.WhenAll(itemList.Select(item =>
           new WorkToDo(item).StartWork()
           ));
    }
}

public class WorkToDo
{
    private string id;

    public WorkToDo(string id)
    {
        this.id = id;
    }

    public async Task<bool> StartWork()
    {
        Calculate();
        Analyze();
        SomeToDo();
        var result = Save();
        await Task.Delay(100);
        return result;
    }

    private bool Calculate()
    {
        //Some complex and time taking calculation will be here
        return true;
    }

    private bool Analyze()
    {
        //Some complex and time taking calculation will be here
        return true;
    }

    private bool SomeToDo()
    {
        //Some complex and time taking calculation will be here
        return true;
    }

    private bool Save()
    {
        //Some complex and time taking calculation will be here
        return true;
    }
}

Answer 1

您需要记住，正常的async/await仍将在UI线程上执行。

因此，为了确保一个真正的长操作被推送到后台线程，您需要将其封装在task.run...liketask.run(()=>task.whenall（任务））；

为了更多地完成这个问题（查看其他可用的答案），task.run的用法不能掉以轻心。这完全取决于需要包装什么样的代码。在Stephen Cleary的博客http://blog.stephencleary.com/2013/11/taskrun-itectorial-examples-even-in.html上有一个很好的写作系列，所以花点时间浏览一下，看看什么适合你的项目。