How to configure multiple domain on single Google Analytics account

Question

I'm upgrading old google analytics code (ga) to latest gtag implementations.

in the old implementation we were using couple of site under one account using below command,

ga('create', '<TrackingID>', '<DomainName>');

but in the new implementation we are required to use

gtag('config', '<TrackingID>');

I managed to get google tracking working using the provided code by google, but I had to create two properties with different urls,

Is there a way to record analytics from both sites under same property.

Also in the old implementation we were able to push javascript function as below,

var _gaq = _gaq || [];
_gaq.push(['_setAccount', '<TrackingID>', '<Domain>']);
_gaq.push(['_trackPageview']);
_gaq.push(function () {
    foo(1000);
});

Is there a way to push function using "gtag"?

Thanks

Answer 1

With gtag.js you can use following code:

gtag('config', 'GA_MEASUREMENT_ID', {
  'linker': {
    'domains': ['example.com']
  }
});

https://developers.google.com/analytics/devguides/collection/gtagjs/cross-domain