Passing vector<double> over to Javascript

[joelhnatow]

Hi,

I'm working on a project where in my C++ native app I'm going to be passing over a vector<double> with roughly ~10,000 to ~20,0000 doubles in it to my Javascript layer, which in turns expects a Javascript array. I see two options now to get that data over there - convert that vector to a string and just simply call ExecuteJavascript() (and then JSON.Parse() it) or use CefV8Value::CreateArray and then populate the array with CefV8Value::CreateDouble for each double in the vector and then use SetValue() to set it to the window object. My questions are 1) is there any other (better) way to get this data to the JS side and 2) if not is there any real performance benefit from using the native JS types that CEF provides over just pumping big strings in via ExecuteJavascript()?

Thanks!

[magreenblatt]

is there any real performance benefit from using the native JS types that CEF provides over just pumping big strings in via ExecuteJavascript()?

Sounds like something that would be easy to benchmark. Maybe you can tell us which is better .

[joelhnatow]

Fair enough, I will do that! Did I miss any other method (short of using websockets or something somewhat external to CEF) to get data like this from point A to point B?

[magreenblatt]

:D Fair enough, I will do that! Did I miss any other method (short of using websockets or something somewhat external to CEF) to get data like this from point A to point B?

You could use a custom resource handler to return the JSON via the network stack. See https://bitbucket.org/chromiumembedded/ ... t-handling

[joelhnatow]

:D Fair enough, I will do that! Did I miss any other method (short of using websockets or something somewhat external to CEF) to get data like this from point A to point B?

You could use a custom resource handler to return the JSON via the network stack. See https://bitbucket.org/chromiumembedded/ ... t-handling

Unfortunately I didn't follow how this would be able to get this data from the native C++ app over to JS-land...

However, for anyone who is curious, from my testing/benchmarking, it appears that just converting the vector<double> to a huge JSON string and calling ExecuteJavaScript() in my C++ app is ~2x faster vs. converting everything to Cef ListValue types/sending an IPC message/converting to CefV8Value/passing over to the JS world.

This came in handy to optimize the conversion from double-string - https://github.com/miloyip/dtoa-benchmark

HTH someone / Thanks for the help!