Question

I implemented an activeX control with Delphi. Now I want to add an events for it. I use the type library editor to add the event like this.

procedure OnActionMethod(ActionType: Integer; x1: Integer; 
  y1: Integer; x2: Integer; y2: Integer; param1: Double); dispid 213;

TezDICOMXOnActionMethod = procedure(ASender: TObject; 
  ActionType: Integer; x1: Integer; y1: Integer; x2: Integer; y2: Integer; 
  param1: Double) of object;

Everything compile fine.

Now I build a C# application, use that ActiveX control and try to implement an event handler.

private AxezDICOMax.AxezDICOMX the_ezdicom; // this is the activeX object

public void onActionHandler(object sender,long actiontype, 
    long x1, long y1, long  x2,long  y2, double param1)
{
  MessageBox.Show("abcabc" + x1.ToString() + x2.ToString());
}

private void MainForm_Load(object sender, System.EventArgs e)
{           
  the_ezdicom.OnActionMethod += new 
    AxezDICOMax.IezDICOMXEvents_OnActionMethodEventHandler(this.onActionHandler);
}

But the compiler complains with this error

Error 1  No overload for 'onActionHandler' matches delegate 
  'AxezDICOMax.IezDICOMXEvents_OnActionMethodEventHandler'
  OnActionMethodEventHandler

What did I do wrong? I didn’t find the OnActionMethodEventHandler() anywhere on my Delphi source.

Answer 1

I use the auto – completion feature of Visual studio to know the true method should be.

void  onActionHandler(object sender, AxezDICOMax.IezDICOMXEvents_OnActionMethodEvent e)
{
    MessageBox.Show("abc");
}