sorting using php

I brought all values from the db and showed them on a page. Now, if I click the column it should sort ascending or descendi开发者_Go百科ng.

How do I do this?

If you want to do this solely in PHP you will need to add parameters onto the query string in the URL.

www.example.com/table.php?col=mycolumn&sort=desc

That would be in the anchor tag for that column, then in table.php you would have the logic to handle sorting.

You'll be using JavaScript. I suggest sorttable.

Expanding on roflwaffle's post, you will want to use query string vars. From these build a string which you add into your query.

$querySort = array();
if (isset($_GET['colName'])) {
    $s = $_GET['colName'];
    $snext = '';
    switch ($s) {
        case '':     $snext = 'desc'; break;
        case 'desc': $snext = 'asc';  break;
        case 'asc':  $snext = ''; break;
        default:     $snext = '';
    }
    if (!empty ($snext)) {
        $querySort[] = "colName $snext";
    }
    $colName_link = "colName=$snext";
    $colName_text = $snext;
}

// Further column checks

if (count($querySort) == 0) {
    // Default sort if no sort is given.
    $querySort[] = "colName asc";
}

$sort = implode (', ', $querySort);

$query = mysql_query ("SELECT * FROM table ORDER BY $sort");

So given the following query string,

www.example.com/table.php?colName=desc  

the query would look like this

SELECT * FROM table ORDER BY colName desc LIMIT 0, 15

and the category link would look like this

echo "<a href='?$colName_link'>Column Name</a> <small>$colName_text</small>";

The best way to do this is by using javascript(no need to refresh page). Yahoo!'s YUI3 has a very nice datatable component. I can not make up from your question if you got the complete dataset on your PHP page but I will assume this for now. You should have a look at YUI3's Column Sorting page to get you started.

Please take a look at THIS link.Check the Example HERE. I use it in one of my project for the same purpose , hope it will help you too.

request: www.example.com/table.php?col=mycolumn&sort=desc

//may be some check , about the column is in  the table field
//sort is in the set of (asc , desc)

$q = "select * from mytable where mycond order by addslashes($_GET['mycolumn']) addslashes($_GET['sort'])";