Producing snippets of text

Like G does in SERPs

[ThomasB]

I currently have the following code:

$select = "SELECT * FROM text WHERE MATCH(content) AGAINST ('".$keyword."') LIMIT 0,50";

$query = mysql_query($select);

while ($info = mysql_fetch_object($query)) {
$results[] = $info->content;
}

foreach($results as $result) {

echo $result."<br> ";

};

This works pretty well. But I'd like to have snipptes only.
ie
keyword = "new books"
content = "I recently read a new article about information that was published in books a long time ago."
result = "... read a new article about ... published in books a long ..."

Any ideas how to perform this task?

[Lord Majestic]

How about this: use regular expressions to "highlight" matches (new, books) with <b>'s and then identify positions of <b>'s and allow up to X characters before each match with some additional constraints to avoid having too much text.

Another way to do it would be split whole text into words, then walk word by word checking if its a match in which case take last and next X words for snippet's purposes.

Can't say whether its the ideal way to do it (I am yet to implement it for my search engine) but it should work well for 10-20 displayed matches :)

[jatar_k]

or maybe some combination of strpos, count_chars and explode on spaces

which would essentially give you the word position in the string and then allow you to output words before and after your given position/word.