c# - 向此类添加委托(delegate)或事件属性？

Question

我创建了一个控件，其他开发人员可以在其中创建实例并使用。控件中有一个按钮单击。我如何允许开发人员在我的控件的某个部分插入他们自己的代码？我不确定在这种情况下是否或如何使用委托(delegate)或事件。有人可以在下面的例子中提供帮助吗:

public class MyControl : CompositeControl
{
   ...
   void btnSubmit_Click(object sender, EventArgs e)
   {
      //DO SOMETHING
      if (success)
      {
         //CALL DEVELOPER'S LOGIC
      }
   }
}

在开发者的代码中，当控件的按钮点击成功时，他们如何传入他们的逻辑？

protected override void CreateChildControls()
{
    var ctlMyControl = new MyControl();

    //ADD SuccessCode() TO ctlMyControl
    //SO IT IS TRIGGERED ON SUCCESS
    //MAYBE SOMETHING LIKE:
    //ctlMyControl.SuccessEvent = SuccessCode()??

    this.Control.Add(ctlMyControl);
}

protected void SuccessCode()
{
    //DO SOMETHING
}

如何更新 MyControl 以允许此操作？

Answer 1

您需要添加一个 event到控件，像这样:

void btnSubmit_Click(object sender, EventArgs e) {
    //DO SOMETHING
    if (success) {
        OnSomethingCompleted();
    }
}

///<summary>Occurs when the operation is successfully completed.</summary>
public event EventHandler SomethingCompleted;
///<summary>Raises the SomethingCompleted event.</summary>
internal protected virtual void OnSomethingCompleted() { OnSomethingCompleted(EventArgs.Empty); }
///<summary>Raises the SomethingCompleted event.</summary>
///<param name="e">An EventArgs object that provides the event data.</param>
internal protected virtual void OnSomethingCompleted(EventArgs e) {
    if (SomethingCompleted != null)
        SomethingCompleted(this, e);
}

在表单中，您可以向事件添加处理程序，如下所示:

myControl.SomethingCompleted += myControl_SomethingCompleted;

void myControl_SomethingCompleted(object sender, EventArgs e) {
    //Do things
}

有关详细信息，请参阅 documentation .