How to highlight keywords???

[pantinosm]

Hello everyone. I have a search engine website where i have a textbox that the user input the search string and after pressing the search button i get the results. I want a way the results to be highlighting the words that were in the search textbox just like yahoo and google does. How can i do that?

[Jessica]

look up strpos(), str_replace().

[pantinosm]

can you be a little more specific?

[craygo]

Not sure how you are searching, but you could always look into using css files. if the word is found use a different style. A little code might help if you need help.

Ray

[marcus]

With str_replace(); you could do:

[code=php:0]
$result = $_POST[result];
$result = str_replace($result,"<font style='background-color:yellow;'>$result",$result);
echo $result;
[/code]

[pantinosm]

I now have it like this.
[code]<?php

if(strlen($row_rsfindwebsitesearch['Title'])<60)
{
$result = $row_rsfindwebsitesearch['Title'];
$result = str_replace($result,"<font style='background-color:yellow;'>$result",$result);
echo $result;

}

else echo trim(substr($row_rsfindwebsitesearch['Title'], 0, 60)).'  ...';


?>[/code]

The problem now is tht i highlight the whole sentence instead of the search string.
I dont know if it is appropriate but you can see the result at ibeba.com

[Eddyon]

have you tried putting </font> after the result?

[pantinosm]

Yes like this  $result = str_replace($result,"<font style='background-color:yellow;'>$result</font>",$result);

and same result  :(

[pantinosm]

It highlights all the line because it is the result. I understand this. But how can i highlight only the search words???

Please help. 

[GingerRobot]

Well it looks to me like you are searching for the whole of the text within the variable result, and you are searching within the same variable, so it will replace the whole thing.

Here is a sample of how you should use it, im not using your variables because i dont know what they are

[code]
<?php
$text = "A test sentence";
$search_term = "test";
$output = str_replace($search_term,"<font style='background-color:yellow;'>$search_term</font>",$text);
echo $output;
?>
[/code]

So you look for the search term, replace it with the search term against a background in yellow, but you look for the search term within the whole text.

[tuuga]

or

[CODE]
<?php

function highlight($str, $rep) {
        $begin = '<span style="background-color:yellow">';
        $end = '</span>';
        $color = $begin.$rep.$end;
        return eregi_replace($rep, $color, $str);
}


$str = 'some text, some text, some text, some text, some text, some text';
$strRep = 'some';

$str = highlight($str, $strRep);
echo $str;

?>
[/CODE]

[GingerRobot]

Yes, you could always set up a function. However, you shouldn't use ereg_replace or preg_replace for this kind of thing, str_replace(or str_ireplace if you want it to be case insensitive) is faster. The other two should be used if you want to use regular expressions.

[pantinosm]

Thank you very much GingerRobot it worked. But it only works with one word as the search term. Is the a way to highlight any word in the search term. E.g if the search term is "test query" it should highlight query individually and test individually.

Can it be done?

[Nicklas]

http://www.phpfreaks.com/forums/index.php/topic,115226.msg469086.html#msg469086

[Nicklas]

do something like this if you want to highlight them individually:

[CODE]<?php

function highlight($str) {
$tmp = '';

foreach(explode(' ', $str) as $word)
$tmp .= "<span style=\"background-color:yellow\">$word</span> ";

return trim($tmp);

}

$query = "test query";
$string = "hello there, this is a test query";

echo preg_replace("/$query/ise", 'highlight("\\0")', $string);

?>[/CODE]

[pantinosm]

Thank you Nicklas but where is $tmp used in preg_replace??
I didn't understand.

[Nicklas]

the preg_replace call the function highlight() and takes the match, split it and then surround each word with a <span> tag. Then the string is put back together via the $tmp variable and return it to preg_replace().

[pantinosm]

Yes but why you call the highlight function with highlight("\\0")? Where do you send the string?

[pantinosm]

Because now the keywords in the result instead of highlight they get replaced with "highlight ("keywords")" string!!!!

[Nicklas]

[quote]why you call the highlight function with highlight("\\0")?[/quote]

\\0 is a backreference and holds the matched keyword(s)

[quote]Because now the keywords in the result instead of highlight they get replaced with "highlight ("keywords")" string!!!![/quote]

Show me your code.

[pantinosm]

The code is [code]
<?php
function highlight($str) {
$tmp = '';

foreach(explode(' ', $str) as $word)
$tmp .= "<span style=\"background-color:pink\">$word</span> ";

return trim($tmp);

}
?>

<?php
$result = $row_rsfindwebsitesearch['Description'];
$searchterm = $_GET['txtsearch'];

echo preg_replace("/$searchterm/is", 'highlight("\\0")',  $result);

  ?>
[/code]

What am i doing wrong?

[Nicklas]

The [b]e[b] modifier is missing in preg_replace()

change to this:

[code=php:0]echo preg_replace("/$searchterm/ise", 'highlight("\\0")',  $result);[/code]

[pantinosm]

Thank you that worked. The only thing now is that i want to make it case in-sensitive. Is there any way of doing that?

[pantinosm]

The problem is that i get the highlighted resultls in 70% right. Some keywords are not highlighted all the time. I can see the same keyword somewhere highlighted and somewhere not. Is this a bug or something?