Convert HTML To ASCII With PHP

26th April 2008 - 2 minutes read time

Note: This post is over a year old and so the information contained here might be out of date. If you do spot something please leave a comment and I will endeavour to correct.

The reverse of turning ASCII text into HTML is to convert HTML into ASCII. And to this end here is a little function that does this.

function html2ascii($s) {
 // convert links
 $s = preg_replace('/<a\s+.*? href="?([^\">]*)"?[^>]*>(.*?)<\/a>/i','$2 ($1)',$s);
 
 // convert p, br and hr tags
 $s = preg_replace('@<(b|h)r[^>]*>@i',"\n",$s);
 $s = preg_replace('@<p[^>]*>@i',"\n\n",$s);
 $s = preg_replace('@<div[^>]*>(.*)@i',"\n".'$1'."\n",$s);  
 
 // convert bold and italic tags
 $s = preg_replace('@<b[^>]*>(.*?)@i','*$1*',$s);
 $s = preg_replace('@<strong[^>]*>(.*?)@i','*$1*',$s);
 $s = preg_replace('@<i[^>]*>(.*?)@i','_$1_',$s);
 $s = preg_replace('@<em[^>]*>(.*?)@i','_$1_',$s);
 
 // decode any entities
 $s = strtr($s,array_flip(get_html_translation_table(HTML_ENTITIES)));
 
 // decode numbered entities
 $s = preg_replace('/&#(\d+);/e','chr(str_replace(";", "", str_replace("&#","","$0")))', $s);
 
 // strip any remaining HTML tags
 $s = strip_tags($s);
 
 // return the string
 return $s;
}

To use this function just pass it a string. Here is an example of it at work.

$htmlString = '<p>This is some <strong>XHTML</strong> markup that <em>will</em> be<br />
turned <a href="http://www.hashbangcode.com/" title="#! code">into</a> an ascii string.</p>';
 
echo html2ascii($htmlString);

Produces the following output.

This is some *XHTML* markup that _will_ be
turned into (http://www.hashbangcode.com/) an ascii string

PHP

Comments

Permalink

I got error at in line 19 --> $s = preg_replace('//e','chr(\\1)',$s); Warning: Wrong parameter count for chr() in C:\PHP-test\xxxxx.php (??) : regexp code on line 1

Permalink

You are quite right, that would never work! I have updated the script with the fix.

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