Auto Naming Custom Doctype

I created a doctype. In this doctype there is a custom field for the date.
I want the entries to be named: owner + custom_date

I can name an entry like the owner with “field:owner”. But how can I concat 2 fields?

You need to write a autoname function in server side controller. For reference, please check erpnext/ at develop · frappe/erpnext · GitHub

I am using the software as a service version of ERPNext. I cannot write a server side function.
Are there other possibilities?

Hi Nabin,

So if I want to name a BOM based on the item code and project name (BOM-itemcode-projectcode), I need to alter the autoname function in right? Is there anything else I would have to modify in the code?