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16.4 Push Buttons

401

Core Warning

Netscape does not support the 

BUTTON

 element.

Submit Buttons

HTML Element:

 (No End Tag)

Attributes:

NAME

, 

VALUE

, 

ONCLICK

,

 ONDBLCLICK

, 

ONFOCUS

, 

ONBLUR

When a submit button is clicked, the form is sent to the servlet or other

server side program designated by the 

ACTION

 parameter of the 

FORM

.

Although the action can be triggered other ways, such as the user clicking on

an image map, most forms have at least one submit button. Submit buttons,

like other form controls, adopt the look and feel of the client operating sys 

tem, so will look slightly different on different platforms. Figure 16 11 shows

a submit button on Windows 98, created by

Figure 16 11 A submit button with the default label.

NAME and VALUE

Most input elements have a name and an associated value. When the 

form is submitted, the names and values of active elements are concate 

nated to form the data string. If a submit button is used simply to ini 

tiate the submission of the form, its name can be omitted and then it 

does not contribute to the data string that is sent. If a name is supplied, 

then only the name and value of the button that was actually clicked are 

sent. The label is used as the value that is transmitted. Supplying an 

explicit 

VALUE

 will change the default label. For instance, the following 

code snippet creates a textfield and two submit buttons, shown in Fig 

ure 16 12. If, for example, the first button is selected, the data string 

sent to the server would be 

Item=256MB+SIMM&Add=Add+Item+to+Cart

.

Item:

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