Hi EO Support!

Interesting observation here. I can see that in cases where my javascript uses the JSExtInvoke mechanism from multiple simultaneous threads (e.g. from > 1 ajax callback) sometimes the JSObjects coming over are missing properties. The first time I call the Item method on JSObject it returns the value sent by the javascript, but sometimes the second call returns null. I've confirmed that the javascript is publishing a real value as expected. Important to note that the 2nd property is supposed to be a JSArray. Also of note is that when I set a breakpoint for when this condition occurs, if I try to watch the JSObject's Item method the evaluation times out.

When I cut down on the number of simultaneous JSExtInvoke calls it seems to help mitigate this issue.

Is there a possible thread safety issue in play here with the javascript-to-.Net bridge?

Example of .Net code receiving the JSExtInvokeArgs:
var jsObject = e.Arguments[0] as JSObject;
var property1 = jsObject["contextObjectName"]; //always works
var property2WhichIsAnArray = jsObject["contextPropertyArray"]; // sometimes null even though the javascript object has it. when I try to Watch in the debugger evaluation times out.

example of what the javascript object looks like:
{contextObjectName:"SomeEventOccurred",contextPropertyArray:[{contextPropName:"InfoAboutTheEvent",contextPropValue:{"Property1":"Some Value","Property2":false}}]}

Hey Folks,

Just a quick update. I am working to find time to create a sample project (difficult with so many competing priorities!). Also, wanted to inform you that this issue came up when I upgraded to 16.2.23 but does not appear to be present in 16.2.1. For now, I've rolled back to 16.2.1.

JK

Hi,

This is just to let you know that we have found the root of the problem. Since we are at the end of 2016 release cycle, the fix will probably be in the first 2017 build, which should come out in January. The new build is covered by your current license. We will reply again once the new build is posted.

Thanks!

You are welcome and your test app was very helpful in reproducing the problem. Please feel free to let us know if you run into any other problems in the future.

Hi All,

I updated to 17.0.31 and ran with the sample project that I sent to you. Now, the navigation task simply hangs when calling WebView's LoadUrl method. Please advise.

Thanks,

JK

Thanks for the quick response.

In my "Navigate" method I've got some code that is waiting for WebView.StatusMessage to change. That is not happening.

So, if I remove that StautsMessage-related code, then it comes to this block of code, and the OnDone handler of the NavigationTask never fires and the page never loads:
var navigationTask = this.webBrowserControl.WebControl.WebView.LoadUrl(url);
navigationTask.WaitOne(30000);
navigationTask.OnDone(...

Let me know if there's any other diagnostics I can provide or if you'd like my updated sample project. Thanks!

Same behavior confirmed by another person on another machine.

We are still not able to reproduce the problem. Does TabbedBrowser sample application works on your system?

Hi,

Please download build 17.0.40 from our download page and see if it resolves the issue for you. This build fixed an issue that maybe the root of the problem for your case.

Thanks!

Glad to hear that! Please feel free to let us know if you see any other issues.