onkeypress Event

Fires when the user presses an alphanumeric key.

dhtml语法

Inline HTML <ELEMENT onkeypress = "handler" ... > All platforms
Event property object.onkeypress = handler JScript only
object.onkeypress = GetRef("handler") Visual Basic Scripting Edition (VBScript) 5.0 or later only
Named script <SCRIPT FOR = object EVENT = onkeypress> Internet Explorer only

Event Information

Bubbles Yes
Cancels Yes
To invoke Press any alphanumeric keyboard key.
Default action Returns a number specifying the Unicode value of the key that was pressed.

Event Object Properties

Although event handlers in the DHTML Object Model do not receive parameters directly, a handler can query an event object for data.
available properties
altKey Sets or retrieves a value that indicates the state of the ALT key.
altLeft Sets or retrieves a value that indicates the state of the left ALT key.
cancelBubble Sets or retrieves whether the current event should bubble up the hierarchy of event handlers.
clientX Sets or retrieves the x-coordinate of the mouse pointer's position relative to the client area of the window, excluding window decorations and scroll bars.
clientY Sets or retrieves the y-coordinate of the mouse pointer's position relative to the client area of the window, excluding window decorations and scroll bars.
ctrlKey Sets or retrieves the state of the CTRL key.
ctrlLeft Sets or retrieves the state of the left CTRL key.
keyCode Sets or retrieves the Unicode key code associated with the key that caused the event.
offsetX Sets or retrieves the x-coordinate of the mouse pointer's position relative to the object firing the event.
offsetY Sets or retrieves the y-coordinate of the mouse pointer's position relative to the object firing the event.
returnValue Sets or retrieves the return value from the event.
screenX Retrieves the x-coordinate of the mouse pointer's position relative to the user's screen.
screenY Sets or retrieves the y-coordinate of the mouse pointer's position relative to the user's screen.
shiftKey Sets or retrieves the state of the SHIFT key.
shiftLeft Retrieves the state of the left SHIFT key.
srcElement Sets or retrieves the object that fired the event.
type Sets or retrieves the event name from the event object.
x Sets or retrieves the x-coordinate, in pixels, of the mouse pointer's position relative to a relatively positioned parent element.
y Sets or retrieves the y-coordinate, in pixels, of the mouse pointer's position relative to a relatively positioned parent element.

Remarks

As of Microsoft® Internet Explorer 4.0, the onkeypress event fires and can be canceled for the following keys:
Letters: A - Z (uppercase and lowercase)
Numerals: 0 - 9
Symbols: ! @ # $ % ^ & * ( ) _ - + = < [ ] { } , . / ? \ | ' ` " ~
System: ESC, SPACEBAR, ENTER

DHTML代码范例

This example shows how to retrieve information from the shiftKeyihtmleventobj2::shiftkey property of the event object. when the user simultaneously presses the shift key and types a character in the first text field, the value "true" appears in the second text field.
<HEAD>
<SCRIPT>
function checkKey()
{
if (window.event.shiftKey)  // checks whether the SHIFT key
// is pressed
{
txtOutput.value = "true"; // returns TRUE if SHIFT is pressed
// when the event fires
}
}
</SCRIPT>
</HEAD>
<BODY>
<P>Press the SHIFT key while pressing another key.<BR>
<INPUT TYPE=text NAME=txtEnterValue onkeypress="checkKey()">
<P>Indicates "true" if the shift key is used.<BR>
<INPUT TYPE=text NAME=txtOutput>
</BODY>
This feature requires Microsoft® Internet Explorer 4.0 or later. Click the following icon to install the latest version. Then reload this page to view the sample.

是否符合公共标准

This event is defined in HTML 4.0 .

Applies To

A, ACRONYM, ADDRESS, APPLET, AREA, B, BDO, BIG, BLOCKQUOTE, BODY, BUTTON, CAPTION, CENTER, CITE, CODE, CUSTOM, DD, DEL, DFN, DIR, DIV, document, DT, EM, FIELDSET, FONT, FORM, hn, HR, I, INPUT type=button, INPUT type=checkbox, INPUT type=file, INPUT type=image, INPUT type=password, INPUT type=radio, INPUT type=reset, INPUT type=submit, INPUT type=text, KBD, LABEL, LEGEND, LI, LISTING, MAP, MARQUEE, MENU, nextID, NOBR, OBJECT, OL, P, PLAINTEXT, PRE, Q, RT, RUBY, S, SAMP, SELECT, SMALL, SPAN, STRIKE, STRONG, SUB, SUP, TABLE, TBODY, TD, TEXTAREA, TFOOT, TH, THEAD, TR, TT, U, UL, VAR, XMP

更多语法参考

onchange, onkeydown, onkeyup