如何为事件定义自定义事件参数

Question

我想为一系列事件创建自定义事件参数。我正在使用第三方 X/Y 示波器，在其中绘制强度与频率。 该示波器能够在其上放置"标记"，这些标记只是不同频率的小三角形。 这些标记支持诸如鼠标进入标记、执行单击以及鼠标离开标记时等事件。 因此，对于两个标记，这是代码：

        private void createEvents()
        {
            this.scope2.MarkerGroups[0].Click += new EventHandler(Marker0_Click);
            this.scope2.MarkerGroups[0].MouseEnter += new EventHandler(Marker0_Enter);
            this.scope2.MarkerGroups[0].MouseLeave += new EventHandler(Marker0_Leave);
            this.scope2.MarkerGroups[1].Click += new EventHandler(Marker1_Click);
            this.scope2.MarkerGroups[1].MouseEnter += new EventHandler(Marker1_Enter);
            this.scope2.MarkerGroups[1].MouseLeave += new EventHandler(Marker1_Leave);
        }
        // And now the event handlers
        private void Marker0_Click(object sender, EventArgs e)
        {
            //do something;           
        }
        private void Marker0_Enter(object sender, EventArgs e)
        {
              //do something          
        }
        private void Marker0_Leave(object sender, EventArgs e)
        {
            // do something
        }
        private void Marker1_Click(object sender, EventArgs e)
        {
            //do something;           
        }
        private void Marker1_Enter(object sender, EventArgs e)      
        {
              //do something          
        }
        private void Marker1_Leave(object sender, EventArgs e)
        {
            // do something
        }

现在这对两个标记来说很好....但我需要其中的 80 个。 我可以把整个事情写出来，但必须有更好的方法。 所以我是这样开始的：

    private void createMarkerEvents()
    {
        for (int i = 0; i < 80; i++)
        {
            this.scope2.MarkerGroups[i].Click += new EventHandler(Marker_Click);
            this.scope2.MarkerGroups[i].MouseEnter += new EventHandler(Marker_Enter);
            this.scope2.MarkerGroups[i].MouseLeave += new EventHandler(Marker_Leave);
        }
     }
        private void Marker_Click(object sender, EventArgs e)
        {
            //do something;           
        }
        private void Marker_Enter(object sender, EventArgs e)
        {
              //do something          
        }
        private void Marker_Leave(object sender, EventArgs e)
        {
            // do something
        }

所以问题是如何将实际的标记编号从事件传递到事件处理程序？一定有办法。谢谢，汤姆

Answer 1

如果要标识标记组，可以将object sender强制转换为MarkerGroup对象

private void AnyMarker_Click(object sender, EventArgs e)
{
    MarkerGroup group = (MarkerGroup)sender;
    int indexOfMarkerGroup = this.scope2.MarkerGroups.IndexOf(group);
    //do something;           
}

OFF：您应该定义一个自定义的 EventArgs 类：

public class MyEventArgs : EventArgs
{
    public int MyCustomProperty {get;set;}
}

然后在您的活动中使用它：

public event EventHandler<MyEventArgs> ButtonPressed;

使用自定义参数的火灾事件：

if(ButtonPressed != null)
{
    ButtonPressed(this, new MyEventArgs { MyCustomProperty = 1 });
}

编辑完整示例：

private void createMarkerEvents()
{
    for (int i = 0; i < 80; i++)
    {
        this.scope2.MarkerGroups[i].Click += new EventHandler(Marker_Click);
        this.scope2.MarkerGroups[i].MouseEnter += new EventHandler(Marker_Enter);
        this.scope2.MarkerGroups[i].MouseLeave += new EventHandler(Marker_Leave);
    }
 }
 private void Marker_Click(object sender, EventArgs e)
 {
     // When markergroup fires and event, it passes reference to itself as `sender` parameter
     // so we can get access it
     MarkerGroup mg = (MarkerGroup)sender; // this marker has fired a click event
     // Now you know which marker has fired event
     // if you want to determine it's index in MarkerGroups collection:
     int index = this.scope2.MarkerGroup.IndexOf(mg);
     // now you know MarkerGroup and it's index
 }
 private void Marker_Enter(object sender, EventArgs e)
 {
    //do something          
 }
 private void Marker_Leave(object sender, EventArgs e)
 {
    // do something
 }