DHTML Events
Fires when a key is pressed and released over an element.
| Inline HTML |
<element onkeypress = "handler" ... > |
All platforms |
| Event property |
object.onkeypress = handler |
ECMA-262 Language Specification |
| Named script |
<script FOR=object EVENT=onkeypress> |
Internet Explorer® only |
| Bubbles |
Yes |
| Cancels |
Yes |
| To invoke |
Press a keyboard key. |
| Default action |
Returns a number specifying the Unicode value of the key that was pressed. |
Setting event.returnValue=false has no effect on keyboard events used for navigation, on hot keys assigned to the browser, or on system events. The following keys cannot be canceled: TAB, F1 through F12, HOME, END, ESC, DELETE, and the arrow keys.
While event handlers in the Document Object Model do not receive parameters directly, the handler can query the event object for data.
Event Object Properties
| altKey |
Retrieves the current state of the ALT key. |
| cancelBubble |
Sets or retrieves whether the current event should bubble up the hierarchy of event handlers. |
| clientX |
Retrieves the x-coordinate of the position of the cursor when the mouse is clicked, relative to the size of the client area of the window but excluding window decorations or scroll bars. |
| clientX |
Returns the y-coordinate of the position of the cursor when the mouse is clicked, relative to the size of the client area of the window but excluding window decorations or scroll bars. |
| ctrlKey |
Retrieves the state of the CTRL key. |
| keyCode |
Sets or retrieves the Unicode key code associated with the key that caused the event. |
| offsetX |
Retrieves the horizontal coordinate of the mouse's position relative to the object firing the event. |
| offsetX |
Retrieves the vertical coordinate of the mouse's position relative to the object firing the event. |
| returnValue |
Sets or retrieves the return value from the event. |
| screenX |
Retrieves the horizontal position of the mouse, in pixels, relative to the user's screen. |
| screenY |
Retrieves the vertical position of the mouse, in pixels, relative to the user's screen. |
| shiftKey |
Retrieves the state of the SHIFT key. |
| srcElement |
Retrieves the object that fired the event. |
| type |
Retrieves the event name from the event object. |
| x |
Returns the horizontal position of the mouse when the event fires. |
| y |
Returns the vertical position of the mouse when the event fires. |
The onkeypress example shows how to retrieve information from the shiftKey property of the event object.
Sample Code
<head>
<script language="JavaScript">
function checkKey ( ) {
txtEnterValue.focus();
if (window.event.shiftKey)
txtOutput.value = "true";
else
txtOutput.value = "false";}
</script>
</head>
<body>
<div align="center">
<input size=10 name=txtEnterValue
onkeypress="checkKey()">
<br><br>
Returns "true" if the shift key is used,
and "false" if not.<br>
<input size=10 name=txtOutput readOnly></div>
</body>
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This attribute may be used with most elements.
onchange, onkeydown, onkeyup
