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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
*/
<!-- This file implements a navigation bar, designed to go in a frame at
the bottom of a window. Include it in a frameset like the following:
<frameset rows="*,75">
<frame src="about:blank">
<frame src="navigation.html">
</frameset>
-->
<script>
// The function is invoked by the Back button in our navigation bar.
function go_back()
{
// First, clear the URL entry field in our form.
document.navbar.url.value = "";
// Then use the History object of the main frame to go back.
parent.frames[0].history.back();
// Wait a second, and then update the URL entry field in the form
// from the location.href property of the main frame. The wait seems
// to be necessary to allow the location.href property to get in sync.
setTimeout("document.navbar.url.value = parent.frames[0].location.href;",
1000);
}
// This function is invoked by the Forward button in the navigation bar.
// It works just like the one above.
function go_forward()
{
document.navbar.url.value = "";
parent.frames[0].history.forward();
setTimeout("document.navbar.url.value = parent.frames[0].location.href;",
1000);
}
// This function is invoked by the Go button in the navigation bar, and also
// when the form is submitted (when the user hits the Return key).
function go_to()
{
// Just set the location property of the main frame to the URL
// that the user typed in.
parent.frames[0].location = document.navbar.url.value;
}
</script>
<!-- Here's the form, with event handlers that invoke the functions above. -->
<form name="navbar" onsubmit="go_to(); return false;">
<input type="button" value="Back" onclick="go_back();">
<input type="button" value="Forward" onclick="go_forward();">
URL:
<input type="text" name="url" size="50">
<input type="button" value="Go" onclick="go_to();">
</form>
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