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我在将自定义事件从 vb.net 转换为 c# 时遇到了一些问题，我真的没有 vb.net 的经验，而且我对这些自定义事件的经验更少，应用程序的其余部分被转换没有太多问题，但是这个让我卡住了。我使用的转换器（付费和免费）都未能生成可用代码。

VB.net 代码：

<NonSerialized()> Private _objNonSerializablePropertyChangedHandlers As New System.ComponentModel.EventHandlerList

'''' <summary> 
'''' Raised when a public property of this object is set. 
'''' </summary> 
Public Custom Event PropertyChanged As PropertyChangedEventHandler Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged
    AddHandler(ByVal value As PropertyChangedEventHandler)
        Me.NonSerializablePropertyChangedHandlers.AddHandler(STR_PROPERTYCHANGEDEVENT, value)
    End AddHandler
    RemoveHandler(ByVal value As PropertyChangedEventHandler)
        Me.NonSerializablePropertyChangedHandlers.RemoveHandler(STR_PROPERTYCHANGEDEVENT, value)
    End RemoveHandler
    RaiseEvent(ByVal sender As Object, ByVal e As PropertyChangedEventArgs)

        Dim obj As PropertyChangedEventHandler = TryCast(Me.NonSerializablePropertyChangedHandlers(STR_PROPERTYCHANGEDEVENT), PropertyChangedEventHandler)

        If obj IsNot Nothing Then
            obj.Invoke(sender, e)
        End If

    End RaiseEvent

我已经设法在 c# 中制作的最好的内容如下：

C＃

[NonSerialized()]
private System.ComponentModel.EventHandlerList _objNonSerializablePropertyChangedHandlers = new System.ComponentModel.EventHandlerList();

public event PropertyChangedEventHandler PropertyChanged
{
    add
    {
        this.NonSerializablePropertyChangedHandlers.AddHandler(STR_PROPERTYCHANGEDEVENT, value);
    }
    remove
    {
        this.NonSerializablePropertyChangedHandlers.RemoveHandler(STR_PROPERTYCHANGEDEVENT, value);
    }
}

protected void OnPropertyChanged(string strPropertyName)
{
    EventHandler handler = this.PropertyChanged;
    if (handler != null)
    {
        handler.Invoke(this, new PropertyChangedEventArgs(strPropertyName));
        //PropertyChanged(this, new PropertyChangedEventArgs(strPropertyName));
    }
}

但是，这会引发错误“事件 'CardBase.PropertyChanged' 只能出现在 += 或 -=" 的左侧

上线：EventHandler handler = this.PropertyChanged;

由于我不是 100% 了解上面的代码在做什么，我自己正在努力解决这个问题，如果有人可以帮助我，我将非常感激。

4

1 回答 1

2

更改此代码

protected void OnPropertyChanged(string strPropertyName)
{
    EventHandler handler = this.PropertyChanged;
    if (handler != null)
    {
        handler.Invoke(this, new PropertyChangedEventArgs(strPropertyName));
    }
}

至

protected void OnPropertyChanged(string strPropertyName)
{
    var handler =
       this.NonSerializablePropertyChangedHandlers[STR_PROPERTYCHANGEDEVENT]
           as EventHandler;

    if (handler != null)
    {
        handler(this, new PropertyChangedEventArgs(strPropertyName));
    }
}

参考-event- 只能出现在 += 或 -= 的左侧

于 2013-06-10T11:02:46.637 回答