How to deal the .NET's event with the nodejs event's handler.

[gentlecolder]

the problem code is bellow:
/the edge code bellow: edged.js/
var stractData = edge.func(function () {/*

async (dynamic input) => {
       Box.DataMonitorValueChanged +=input.DataChangedHandler;
}   

*/});

module.exports.stractData=stractData;

/the nodejs code bellow:/
var databox=require('edged.js');

var util = require('util');

var input = {
DataChangedHandler: function (object sender, IList e) {
foreach (DataMonitorValueChangedArgs monitorValue in e)
{

              Console.log(monitorValue.ToString()+";"+monitorValue.Uid.ToString() + ':' +                     monitorValue.Value + '\n');
            }
}

};

databox.stractData(input);

is there any good solution ?

[gentlecolder]

I tried many times as read the instruction:
Func<object, Task> dataChanged=(Func<object, Task>)input.DataChangedHandler;
Box.DataMonitorValueChanged +=await dataChanged;
does it is not suport eventhandler since its delegate is async method?

[gentlecolder]

delegate tag can not submit above "Func<object, Task>"

[gentlecolder]

the erro is cannot wait System.Func<object,System.
Threading.Tasks.Task>
i donot know why?i hope there is a solution which can trans the event result from the .NET to node.js method.

[gentlecolder]

I and i saw .net can handle node events, but node can not handle .net events, that's not fair.

[tjanczuk]

@gentlecolder The functions Edge.js can marshal from JavaScript to C# must have the following signature:

function (data, callback) {
  // ...
  callback(error, result);
}

These functions will then have the shape of the following delegate on the C# side:

Func<object, Task<object>>

If you plan to hook up JavaScript function as a .NET event handler, you will need to provide a wrapper event handler implementation around the marshaled Func<object,Task<object>> in C#.

[gentlecolder]

The debug complied error is:
System.Func<ob
tem.Threading.Tasks.Task >” can not implicit casting “System.EventHandler<System.Collections.Generic.IList >

then i changed the Func<object,Task > to Func<object,Task<System.Collections.Generic.IList > the debug give me the message is "Invalid expression term".
So is there and type need to attention when hook up JavaScript function as a .NET event handler

[gentlecolder]

[gentlecolder]

node Code

C# CODE

[gentlecolder]

it seamed that the node function can not changed to Eventhandler implicitly, why? doest that means Eventhandler is not a function in C#. I am not good at C#

[tjanczuk]

Edge.js does not marshal arbitrary functions between JavaScript and .NET, the functions must be of appropriate signature. It means that in most cases you will need to write an adapter code or class that changes the intended signature of the function: https://github.com/tjanczuk/edge#how-to-integrate-c-code-into-nodejs-code.

In your case, I believe you need to write a wrapper around *EventHandler type expected in your C# code and the Func<object,Task<object>> exposed by Edge.

[gentlecolder]

above code i have showed wrapped still cannot pass complie

[colceagus]

@tjanczuk Could you please provide a simple example of EdgeJS code (Node.JS) code handling .NET events properly?

I want to start an ID Card Reader application (for 3M CR100 SwipeReader) and I want my (edgejs + nodejs) code to listen to the DocumentReadEvent and DocumentReadErrorEvent from my C# code.

I hope you see this asap.

Please reply to this comment just to see you have seen it and if you can apply some action to this issue commented here.

With all due respect,
Daniel.

[colceagus]

@gentlecolder have you been able to assign a javascript event handler to a C# event?

[tjanczuk]

@danielmihai Are you writing .NET application or a Node.js application (i.e. is Node hosted in CLR or vice versa)?

[tjanczuk]

Have a look at https://github.com/tjanczuk/edge/blob/master/samples/209_websocket.js, specifically at how the sendImpl (https://github.com/tjanczuk/edge/blob/master/samples/209_websocket.js#L79) is set up and used to call back to Node.js when something happens in CLR. This example assumes you write a Node.js app and host CLR in it, but the pattern is also applicable if the reverse is true.