document.forms use

Definitions: document.forms form returns the set form, the form containing all of the forms currently DOM structure. 
Syntax: 
    1 . Get the first form current form DOM structure. 
    document.forms [ 0 ]
     2 . Gets the DOM structure specified in the current form form. 
    document.forms [ '' ]; 

Use Case: 
    1 . Gets the current third form DOM structure and form submission. 
    document.forms [ . 3 ] .submit ();
     2 . Gets the current name of the DOM structure hide_name form and submit. 
    document.forms [ ' hide_name ' ] .submit (); 

Note: According to the document describes: get request parameters can not form the action attribute (of the entry is not validated to be temporarily kept in mind.)