EVENT
HANDLER: onFocus
onFocus
= myJavaScriptCode
Event handler for Button, Checkbox,
FileUpload, Layer,
Password, Radio,
Reset, Select,
Submit, Text,
TextArea, Window.
The onFocus event handler executes the specified JavaScript code
or function on the occurance of a focus event. This is when a window,
frame or form element is given focus. This can be caused by the user clicking
on the current window, frame or form element, by using the TAB key to
cycle through the various elements on screen, or by a call to the window.focus
method. Be aware that assigning an alert box to an object's onFocus
event handler with result in recurrent alerts as pressing the 'o.k.' button
in the alert box will return focus to the calling element or object.
The onFocus event handler uses the following Event
object properties.
type - this property indicates the type of event.
target - this property indicates the object to which the event
was originally sent.
The following example shows the use of the onFocus event handler
to replace the default string displayed in the text box. Note that the
first line is HTML code and it is accepted that the text box resides on
a form called 'myForm'.
Code:
<input type="text" name="myText" value="Give me
focus" onFocus = "changeVal()">
<script type="text/javascript" language="JavaScript">
s1 = new String(myForm.myText.value)
function changeVal() {
s1 = "I'm feeling focused"
document.myForm.myText.value = s1.toUpperCase()
}
</script> |