C# 如何在模型/适配器层的长过程中将信息传递到视图层

我试图找到在MVC模型中视图层和模型/适配器层之间来回通信的正确方法。以下是我发行的一些psuedo代码，以及我希望它做什么。有关说明，请参阅MyAdapter.ImportStuff方法中的注释

public class MyView : System.Windows.Forms.UserControl
{
    private MyContoller Ctrl = new MyContoller();
    public MyView()
    {
    }

    private void OnButtonClick()
    {
        Ctrl.DoSqlStuffNow();
        TellUserImportFinished();
    }

    public void TellUserThingsHaveBeenDeleted()
    {
        this.label1.Text = "Stuff deleted...";
    }
    public void TellUserHowManyRowsHaveBeenInserted(int rowCount)
    {
        this.label2.Text = $"Number of rows inserted: {rowCount}...";
    }
    public void TellUserComplexQueriesAreDone()
    {
        this.label3.Text = "Complex queries are done...";
    }
    public void TellUserImportFinished()
    {
        System.Windows.Forms.MessageBox.Show("Success!");
    }
}
internal class MyContoller
{
    MyAdapter Adpt = new MyAdapter();
    internal void DoSqlStuffNow()
    {
        object someParameter = new object();
        Adpt.ImportStuff(someParameter);
    }
}
internal class MyAdapter
{
    internal void ImportStuff(object someParameter)
    {
        SqlConnection sqlConnection = new SqlConnection("connection");

        // All of this has to happen in one connection/transaction.
        // It should not be broken into multiple methods

        DeleteFromTable1();
        DeleteFromTable2();
        // Now I want to tell the user delete is complete!

        MakeTempTable();
        InsertIntoTempTable(someParameter);
        int rowCount = ImportIntoTable1();
        // Now I want to tell the user how many rows were just inserted!

        DoComplexQuery();
        DoAnotherComplexQuery();
        // Now I want to tell the user complex queries are done!

        ImportIntoTable2();
        DropTempTable();
        // Presumably, I can say "success" when this function returns, which is fine
    }
}

我的特殊情况更糟，因为控制器/适配器实际上是静态类，所以处理事件并不有趣，但我甚至不确定在这个简单的情况下如何最好地处理它

---

任何建议都将不胜感激

我不会把事情复杂化。查看您的设计，我将使用适配器类中的事件和

MyView

中的绑定

根据要通知的内容创建4个事件。由于所有事情都发生在一个方法中，所以您还可以有1个事件和4个不同的状态。尽管如此，我不喜欢这种方法，因为它在事件处理程序中需要一堆if

当然，您可以编写自己的委托，但为了简单起见，我确实使用了EventHandler类

    public event EventHandler DeleteCompleted;

    //int: the number of rows inserted
    public event EventHandler<int> RowsInserted;

    public event EventHandler ComplexQuerycCompleted;

    //bool: if the operation completed successfully.
    public event EventHandler<bool> OperationCompleted;

稍后在视图中，您将

MyController

中的属性绑定到用于反映更改的UI控件

阅读有关数据绑定的内容

我不清楚您何时说过“控制器/适配器实际上是静态类”，但我认为上面的内容确实可以帮助您

当然，另一个选择是使用，但这一个需要您以反应式的方式学习Rx.Net和编程

internal class MyAdapter
{

    public event EventHandler DeleteCompleted;

    public event EventHandler<int> RowsInserted;

    public event EventHandler ComplexQuerycCompleted;

    public event EventHandler<bool> OperationCompleted;


    internal void ImportStuff(object someParameter)
    {
        SqlConnection sqlConnection = new SqlConnection("connection");

        // All of this has to happen in one connection/transaction.
        // It should not be broken into multiple methods

        DeleteFromTable1();
        DeleteFromTable2();
        // Now I want to tell the user delete is complete!

        this.DeleteCompleted?.Invoke(this, new EventArgs());

        MakeTempTable();
        InsertIntoTempTable(someParameter);
        int rowCount = ImportIntoTable1();

        // Now I want to tell the user how many rows were just inserted!
        this.RowsInserted?.Invoke(this, rowCount);

        DoComplexQuery();
        DoAnotherComplexQuery();

        // Now I want to tell the user complex queries are done!
        this.ComplexQuerycCompleted.Invoke(this, new EventArgs());

        ImportIntoTable2();
        DropTempTable();

        // Presumably, I can say "success" when this function returns, which is fine
        this.OperationCompleted?.Invoke(this, true);
    }
}

internal class MyContoller : INotifyPropertyChanged
{
    MyAdapter Adpt = new MyAdapter();

    public event PropertyChangedEventHandler PropertyChanged;

    private int rowsInserted;
    public int RowsInserted 
    {
        get { return rowsInserted;}
        set 
        {
            if (rowsInserted == value)
                return;

            rowsInserted = value;
            RaisedPropertyChanged(nameof(RowsInserted));
        }
    }

    internal MyContoller()
    { 
        //Remember to remote the event subscriptions calling:
        // Adpt.RowsInserted -= OnRowsInserted
        Adpt.RowsInserted += OnRowsInserted;
    }

    internal void DoSqlStuffNow()
    {
        object someParameter = new object();
        Adpt.ImportStuff(someParameter);
    }

    /// <summary>
    /// Raiseds the property changed.
    /// </summary>
    /// <param name="propertyName">Property name.</param>
    protected void RaisedPropertyChanged([CallerMemberNameAttribute] string propertyName = "")
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }

    /// <summary>
    /// Called when the Rows has been inserted in the <see cref="MyAdapter"/>
    /// </summary>
    /// <param name="sender">Sender</param>
    /// <param name="numberOfRows">The Number of rows in inserted</param>
    void OnRowsInserted(object sender, int numberOfRows)
    {
        //Notify the UI about objects inserted
        RowsInserted = numberOfRows;
    }
}