In the login interface: the order in which action and onsubmit events are executed in the form form! _form properties and events in a form

In the system, you will often use the form table forms submit data.

Where the action is the property of the form; onsubmit is the event.

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DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" "Http://www.w3.org/TR/html4/loose.dtd" >  

To say the order of execution, onsubmit first, verify that when the validation returns false, the action= "url" address cannot be reached.  If it returns TRUE or does not return a value, the action shifts to the URL address. That is, onsubmit can prevent action from being committed. The return here must be written. Do not write Onsubmit=check ();