创建委托事件

我正在尝试创建一个可以以其他forms访问的委托事件。 但主要forms没有看到能够看到我的代表。 它说代理名称此时无效。 模态forms

public partial class GameOverDialog : Window { public delegate void ExitChosenEvent(); public delegate void RestartChosenEvent(); public GameOverDialog() { InitializeComponent(); } private void closeAppButton_Click(object sender, RoutedEventArgs e) { ExitChosenEvent exitChosen = Close; exitChosen(); Close(); } private void newGameButton_Click(object sender, RoutedEventArgs e) { RestartChosenEvent restart = Close; restart(); Close(); } } 

主要forms：

 private void ShowGameOver(string text) { var dialog = new GameOverDialog { tb1 = { Text = text } }; dialog.RestartChosenEvent += StartNewGame(); dialog.Show(); } private void StartNewGame() { InitializeComponent(); InitializeGame(); } 

在@Fuex的帮助之后 *

 private void ShowGameOver(string text) { var dialog = new GameOverDialog { tb1 = { Text = text } }; dialog.RestartEvent += StartNewGame; dialog.ExitEvent += Close; dialog.Show(); } 

Answer 1

它不起作用，因为delegate void RestartChosenEvent()声明了允许封装方法的引用类型。 所以通过使用它+= StartNewGame给出一个错误。 正确的代码是：

 public partial class GameOverDialog : Window { delegate void myDelegate(); public myDelegate RestartChosenEvent; public myDelegate ExitChosenEvent; public GameOverDialog() { InitializeComponent(); } private void closeAppButton_Click(object sender, RoutedEventArgs e) { ExitChosenEvent(); this.Close(); } private void newGameButton_Click(object sender, RoutedEventArgs e) { RestartChosenEvent(); this.Close(); } } 

然后在你的主窗体中你必须使用StartNewGame ，它是要传递的方法的指针，而不是StartNewGame() ：

 private void ShowGameOver(string text) { var dialog = new GameOverDialog { tb1 = { Text = text } }; dialog.RestartChosenEvent += StartNewGame; dialog.Show(); } 

Answer 2

“委托名称此时无效”错误也可能在您定义委托而不使用new关键字时发生。 例如：

 // In asp.net the below would typically appear in a parent page (aspx.cs page) that // consumes a delegate event from a usercontrol: protected override void OnInit(EventArgs e) { Client1.EditClientEvent += Forms_Client.EditClientDelegate(Client1_EditClientEvent); //NOTE: the above line causes 'delegate name is not valid at this point' error because of the lack of the 'new' keyword. Client1.EditClientEvent += new Forms_Client.EditClientDelegate(Client1_EditClientEvent); //NOTE: the above line is the correct syntax (no delegate errors appear) } 

要将其置于上下文中，您可以在下面看到委托的定义。 在asp.net中，如果您正在定义需要从其父页面（托管控件的页面）获取值的usercontrol，那么您将在usercontrol中定义您的委托，如下所示：

 //this is the usercontrol (ascx.cs page): public delegate void EditClientDelegate(string num); public event EditClientDelegate EditClientEvent; //call the delegate somewhere in your usercontrol: protected void Page_Load(object sender, System.EventArgs e) { if (EditClientEvent != null) { EditClientEvent("I am raised"); } }