php string in to javascript code with comma except last string - php

Question

I'm using a javascript plugin this is the line which I need help from u
<script type="text/javascript">
$('ul#news').newswidget({ source: ['http://rss.news.yahoo.com/rss/us', 'http://rss.news.yahoo.com/rss/world', 'http://feeds.bbci.co.uk/news/rss.xml'],
I would like to add URL data from MySQL
I'm using it with while loop like this
$('ul#news').newswidget({ source:[<?php
while($rssrow = mysql_fetch_array($rss))
{
echo "'"."$rssrow[rss_name]"."'".",";
}
?>],
It doesn't work properly :(.
I need to get like URL,URL,RUL like this.
that means no comma for the last one
any one please help me

Answer 1

You can actually do that pretty easily by a simple reorganization:
if($rssrow = mysql_fetch_array($rss))
{
echo "'".$rssrow['rss_name']."'";
while($rssrow = mysql_fetch_array($rss))
{
// note no quotes -- they are redundant
// prepend the comma
echo ","."'".$rssrow['rss_name']."'";
}
}
It does make for an extra step for the reader, but it does have the benefit of not needing substring, a new array, or a flag.

Answer 2

You could just build the string and remove the last comma:
$result = '';
while($rssrow = mysql_fetch_array($rss))
{
$result .= "'"."$rssrow[rss_name]"."'".",";
}
echo ($result != '') ? substr($result, 0, -1) : "''";
OR use implode():
$result = array();
while($rssrow = mysql_fetch_array($rss))
{
$result[] = $rssrow[rss_name];
}
echo "'" . implode($result, "','") . "'";
(both of these methods will output '' if the result set is empty.)

Answer 3

$urls = "";
while($rssrow = mysql_fetch_array($rss))
{
$urls.= "'$rssrow[rss_name]',";
}
echo substr($urls, 0, -1);

Answer 4

I wonder why no comment points out that you should definitely escape your output. If an entry contains a ', all solutions aside from Dmitry F’s first will break badly.
$('ul#news').newswidget({ source:[<?php
$arr = array();
while($rssrow = mysql_fetch_array($rss))
{
$arr[] = '"' . str_replace('"', '\"', $rssrow['rss_name']) . '"';
}
echo implode(',', $arr);
?>],

Answer 5

here is a little bit different approach:
<?php
$news = array(
'source' => array(
'http://example.com',
'http://example.com'
)
);
$news_json = json_encode($news);
?>
<script>
$('ul#news').newswidget(<?php echo $news_json; ?>);
</script>
another variation:
$url = array();
while($rssrow = mysql_fetch_array($rss))
{
$url[] = '"' . $rssrow['rss_name'] . '"';
}
echo implode(',', $url);