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16.3 Text Controls

397

ted, the form data simply consists of the name and an equal sign (e.g., 

other data&textfieldname=&other data

).

SIZE

This attribute specifies the width of the textfield, based on the average 

character width of the font being used. If text beyond this size is 

entered, the textfield scrolls to accommodate it. This could happen if 

the user enters more characters than the 

SIZE

 or enters 

SIZE

 number 

of wide characters (e.g., capital W) if a proportional width font is being 

used. Netscape automatically uses a proportional font in textfields. 

Internet Explorer, unfortunately, does not, and you cannot change the 

font by embedding the 

INPUT

 element in a 

FONT

 or 

CODE

 element.

MAXLENGTH

MAXLENGTH

 gives the maximum number of allowable characters. This 

number is in contrast to the number of visible characters, which is spec 

ified via 

SIZE

.

ONCHANGE, ONSELECT, ONFOCUS, ONBLUR, 

ONDBLDOWN, ONKEYPRESS, and ONKEYUP

These attributes are used only by browsers that support JavaScript. 

They specify the action to take when the mouse leaves the textfield after 

a change has occurred, when the user selects text in the textfield, when 

the textfield gets the input focus, when it loses the input focus, and 

when individual keys are pressed. 

Password Fields

HTML Element:

(No End Tag)

Attributes:

NAME

 (required), 

VALUE

, 

SIZE

, 

MAXLENGTH

, 

ONCHANGE

, 

ONSELECT

, 

ONFOCUS

, 

ONBLUR

, 

ONKEYDOWN

,

ONKEYPRESS

, 

ONKEYUP

Password fields are created and used just like textfields, except that when the

user enters text, the input is not echoed but instead some obscuring charac 

ter, usually an asterisk, is displayed (see Figure 16 9). Obscured input is use 

ful for collecting data such as credit card numbers or passwords that the user

would not want shown to people who may be near his computer. The regular,

unobscured text is transmitted as the value of the field when the form is sub 

mitted. Since 

GET

 data is appended to the URL after a question mark, you

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