On_submit method of doctype

Hello,

I want to access on_submit method of delivery note through my custom app then what should i do?

are you trying to customize it? If you want to do some additional function on submit of delivery note use hook for it from your app

Check - Hooks

e.g. In your apps hooks.py add this.The function on given path get called while submitting of a delivery note

doc_events = {
	"Delivery Note": {
		"on_submit": "{dotted.path.to.function}",
	}
}

Ok Thank you so much.