Form submission No submit button to solve the idea

Form submission No submit button
I see some forms submitted directly with a picture to submit, the form does not have a submit button or JS commit event. Ask for advice:

This is the DIV that triggers the commit event.

------Solution--------------------
Estimate the use of juqery and the like, late bound events, look for all JS see it
------Solution--------------------
Explore

Estimate the use of juqery and the like, late bound events, look for all JS see it

------Solution--------------------
Control input type= "image" and input type= "Submit"
The effect is "submit"

This is the basic HTML language knowledge

