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/*
Examples From
JavaScript: The Definitive Guide, Fourth Edition
Legal matters: these files were created by David Flanagan, and are
Copyright (c) 2001 by David Flanagan. You may use, study, modify, and
distribute them for any purpose. Please note that these examples are
provided "as-is" and come with no warranty of any kind.
David Flanagan
*/
<html>
<form name="everything"> <!-- A one-of-everything HTML form... -->
<table border="border" cellpadding="5"> <!-- ...in a big HTML table. -->
<tr>
<td>Username:<br>[1]<input type="text" name="username" size="15"></td>
<td>Password:<br>[2]<input type="password" name="password" size="15"></td>
<td rowspan="4">Input Events[3]<br>
<textarea name="textarea" rows="20" cols="28"></textarea></td>
<td rowspan="4" align="center" valign="center">
[9]<input type="button" value="Clear" name="clearbutton"><br>
[10]<input type="submit" name="submitbutton" value="Submit"><br>
[11]<input type="reset" name="resetbutton" value="Reset"></td></tr>
<tr>
<td colspan="2">
Filename: [4]<input type="file" name="file" size="15"></td></tr>
<tr>
<td>My Computer Peripherals:<br>
[5]<input type="checkbox" name="peripherals" value="modem">56K Modem<br>
[5]<input type="checkbox" name="peripherals" value="printer">Printer<br>
[5]<input type="checkbox" name="peripherals" value="tape">Tape Backup</td>
<td>My Web Browser:<br>
[6]<input type="radio" name="browser" value="nn">Netscape<br>
[6]<input type="radio" name="browser" value="ie">Internet Explorer<br>
[6]<input type="radio" name="browser" value="other">Other</td></tr>
<tr>
<td>My Hobbies:[7]<br>
<select multiple="multiple" name="hobbies" size="4">
<option value="programming">Hacking JavaScript
<option value="surfing">Surfing the Web
<option value="caffeine">Drinking Coffee
<option value="annoying">Annoying my Friends
</select></td>
<td align="center" valign="center">My Favorite Color:<br>[8]
<select name="color">
<option value="red">Red <option value="green">Green
<option value="blue">Blue <option value="white">White
<option value="violet">Violet <option value="peach">Peach
</select></td></tr>
</table>
</form>
<div align="center"> <!-- Another table--the key to the one above. -->
<table border="4" bgcolor="pink" cellspacing="1" cellpadding="4">
<tr>
<td align="center"><b>Form Elements</b></td>
<td>[1] Text</td> <td>[2] Password</td> <td>[3] Textarea</td>
<td>[4] FileUpload</td> <td>[5] Checkbox</td></tr>
<tr>
<td>[6] Radio</td> <td>[7] Select (list)</td>
<td>[8] Select (menu)</td> <td>[9] Button</td>
<td>[10] Submit</td> <td>[11] Reset</td></tr>
</table>
</div>
<script>
// This generic function appends details of an event to the big Textarea
// element in the form above. It is called from various event handlers.
function report(element, event) {
var elmtname = element.name;
if ((element.type == "select-one") || (element.type == "select-multiple")){
value = " ";
for(var i = 0; i < element.options.length; i++)
if (element.options[i].selected)
value += element.options[i].value + " ";
}
else if (element.type == "textarea") value = "...";
else value = element.value;
var msg = event + ": " + elmtname + ' (' + value + ')\n';
var t = element.form.textarea;
t.value = t.value + msg;
}
// This function adds a bunch of event handlers to every element in a form.
// It doesn't bother checking to see if the element supports the event handler,
// it just adds them all. Note that the event handlers call report() above.
// Note that we're defining event handlers by assigning functions to the
// properties of JavaScript objects rather than by assigning strings to
// the attributes of HTML elements.
function addhandlers(f) {
// Loop through all the elements in the form
for(var i = 0; i < f.elements.length; i++) {
var e = f.elements[i];
e.onclick = function() { report(this, 'Click'); }
e.onchange = function() { report(this, 'Change'); }
e.onfocus = function() { report(this, 'Focus'); }
e.onblur = function() { report(this, 'Blur'); }
e.onselect = function() { report(this, 'Select'); }
}
// Define some special-case event handlers for the three buttons:
f.clearbutton.onclick = function() {
this.form.textarea.value=''; report(this,'Click');
}
f.submitbutton.onclick = function () {
report(this, 'Click'); return false;
}
f.resetbutton.onclick = function() {
this.form.reset(); report(this, 'Click'); return false;
}
}
// Finally, activate our form by adding all possible event handlers!
addhandlers(document.everything);
</script>
</html>
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