“怎么做?”;定制活动“;在VB.Net中工作?
在C#中,如果我想创建一个“自定义事件”,可以执行以下操作:“怎么做?”;定制活动“;在VB.Net中工作?,.net,vb.net,events,.net,Vb.net,Events,在C#中,如果我想创建一个“自定义事件”,可以执行以下操作: private EventHandler _MyEvent; Public Event EventHandler MyEvent { add{ _MyEvent += value; } remove{ _MyEvent -= Value; } } protected void RaiseMyEvent() { if(_MyEvent != nul) _MyEvent(this, EventArgs.Em
private EventHandler _MyEvent;
Public Event EventHandler MyEvent
{
add{ _MyEvent += value; }
remove{ _MyEvent -= Value; }
}
protected void RaiseMyEvent()
{
if(_MyEvent != nul)
_MyEvent(this, EventArgs.Empty);
}
在VB中,这并不是那么简单,我在网上也找不到任何帮助。
这不起作用:
private _MyEvent as EventHandler
Public Custom Event MyEvent as EventHandler
AddHandler(ByVal value as EventHandler)
_MyEvent += value 'does not work
addhandler _MyEvent, value 'does not work
[Delegate].Combine(_MyEvent, value) '_MyEvent still nothing
End AddHandler
RemoveHandler(ByVal value as EventHandler)
'Same kind of stuff here
End RemoveHandler
RaiseEvent(sender as Object, e as EventArgs)
if(_MyEvent IsNot Nothing) Then '_MyEvent is always nothing
_MyEvent.Invoke(sender, e)
End If
End RaiseEvent
End Event
请提供帮助。委托是不可变的,因此方法“[Delegate].Combine”返回新委托,但不修改参数。因此,您需要:
_MyEvent = [Delegate].Combine(_MyEvent, value)
VB为您从混音中取出大量的工作 只需声明一个事件:
Public Event DidSomething(sender as object, e as EventArgs)
然后在代码中的任意位置调用下降上升事件
RaiseEvent DidSomething(me, EventArgs.Empty)
…现在,如果您(或任何其他人询问)如何创建处理引发事件的方法,请根据“DidSomething”示例执行以下操作:
Private Sub NowDoSomething(sender As Object, e As EventArgs) Handles Me.DidSomething
'Code for Event here
End Sub