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Go Back via JavaScript and PHP

This quick tutorial explains how to use HTML, JavaScript, and/or PHP to enable visitors to “go back” to the previous page. You can use either method to add a simple “go back” link or form button to your web pages.

“Go back” link via HTML & JavaScript

Use this simple code as a button that will return users to the previous page:

<form>
	<input type="button" value="Return to previous page" onClick="javascript:history.go(-1)" />
</form>

Here it is as a simple text link:

<p>
	<a href="javascript:history.go(-1)" title="Return to the previous page">&laquo; Go back</a>
</p>

You can customize the text and attributes as desired.

“Go back” link via PHP, HTML, & JavaScript

You can make things easier by serving PHP and printing the link automatically. Here is the button link:

echo '<form><input type="button" value="Return to previous page" onClick="javascript:history.go(-1)"></form>';

And here is the PHP code to print a “Go back” text link:

echo '<p><a href="javascript:history.go(-1)" title="Return to previous page">&laquo; Go back</a></p>';

As before, customize the text and attributes as desired.

Advanced “go back” technique with PHP

Better yet, you can kick the accessibility factor up a notch by using PHP’s global HTTP_REFERER variable to write explicitly the previous URL, thereby eliminating the JavaScript requirement (thanks to Rick Beckman for the idea):

<?php $referer = filter_var($_SERVER['HTTP_REFERER'], FILTER_VALIDATE_URL);
	
	if (!empty($referer)) {
		
		echo '<p><a href="'. $referer .'" title="Return to the previous page">&laquo; Go back</a></p>';
		
	} else {
		
		echo '<p><a href="javascript:history.go(-1)" title="Return to the previous page">&laquo; Go back</a></p>';
		
	}
?>

The previous code will create an explicit “Go back” link when the referring URL is known. In those awkward situations where no referring URL has been recognized, the function writes a “Go back” link via JavaScript. Note that you can refine the sanitizing function, filter_var() to suit your needs by adding various filter flags.

Jeff Starr
About the Author Jeff Starr = Web Developer. Book Author. Secretly Important.
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5 responses
  1. Rick Beckman March 12, 2007 @ 2:34 pm

    If you are using PHP for it, wouldn’t it be easier to catch the referral URL, if present, and then presenting the link with an actual URL pointer, rather than JavaScript? Accessibility would be helped quite a bit then.

    If no referral URL is set (some users turn it off), a JavaScript-based fallback could be used.

  2. Jeff Starr

    Of course, of course … I was just testing you ;)
    Check out the new, improved version of the article to see your idea in action.
    – Thanks for the catch!

  3. Rick Beckman March 12, 2007 @ 3:49 pm

    You’re welcome!

  4. thank you for the info! works fine…

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