Auto-Complete - autocomplete.js

// ===================================================================
// Author: Matt Kruse <matt@mattkruse.com>
// WWW: http://www.mattkruse.com/
//
// NOTICE: You may use this code for any purpose, commercial or
// private, without any further permission from the author. You may
// remove this notice from your final code if you wish, however it is
// appreciated by the author if at least my web site address is kept.
//
// You may *NOT* re-distribute this code in any way except through its
// use. That means, you can include it in your product, or your web
// site, or any other form where the code is actually being used. You
// may not put the plain javascript up on your site for download or
// include it in your javascript libraries for download.
// If you wish to share this code with others, please just point them
// to the URL instead.
// Please DO NOT link directly to my .js files from your site. Copy
// the files to your server and use them there. Thank you.
// ===================================================================

// -------------------------------------------------------------------
// autoComplete (text_input, select_input, ["text"|"value"], [true|false])
//   Use this function when you have a SELECT box of values and a text
//   input box with a fill-in value. Often, onChange of the SELECT box
//   will fill in the selected value into the text input (working like
//   a Windows combo box). Using this function, typing into the text
//   box will auto-select the best match in the SELECT box and do
//   auto-complete in supported browsers.
//   Arguments:
//      field = text input field object
//      select = select list object containing valid values
//      property = either "text" or "value". This chooses which of the
//                 SELECT properties gets filled into the text box -
//                 the 'value' or 'text' of the selected option
//      forcematch = true or false. Set to 'true' to not allow any text
//                 in the text box that does not match an option. Only
//                 supported in IE (possible future Netscape).
// -------------------------------------------------------------------
function autoComplete (field, select, property, forcematch) {
var found = false;
for (var i = 0; i < select.options.length; i++) {
if (select.options[i][property].toUpperCase().indexOf(field.value.toUpperCase()) == 0) {
found=true; break;
}
}
if (found) { select.selectedIndex = i; }
else { select.selectedIndex = -1; }
if (field.createTextRange) {
if (forcematch && !found) {
field.value=field.value.substring(0,field.value.length-1);
return;
}
var cursorKeys ="8;46;37;38;39;40;33;34;35;36;45;";
if (cursorKeys.indexOf(event.keyCode+";") == -1) {
var r1 = field.createTextRange();
var oldValue = r1.text;
var newValue = found ? select.options[i][property] : oldValue;
if (newValue != field.value) {
field.value = newValue;
var rNew = field.createTextRange();
rNew.moveStart('character', oldValue.length) ;
rNew.select();
}
}
}
}