How to change a basemap to map in EPSG:3826 format

[AbramhumHsu]

Hi:

I am a newbie to ArcGIS javascript. I meet a problem about develop a map application. 

After test and try, I found there must be set basemap in map class first, like following:

  const map = new Map({

                    basemap: "dark-gray" // basemap styles service

                });

But since the project I need to develop now, the basemap is not in gallery, so how to build a basemap first via
tileLayer, and then include this data into basemap, such as following:

  const map = new Map({

                    basemap: "my EPSG:3826 map" // basemap styles service

                });

How to make that, any instructions is highly appreciated, thanks a lot.

[JoelBennett · Accepted solution]

It appears the fourth item listed under the "Creating a Basemap" section of the Basemap module documentation is what you're looking for.