How to make <option selected="selected"> set by MySql and PHP?

Question

How to make <option selected="selected"> set by MySql and PHP?

My code:

echo '<select>';
$tempholder = array();
$rs = mysql_query("SELECT * FROM id ORDER BY year");
$nr = mysql_num_rows($rs);
for ($i=0; $i<$nr; $i++){
    $r = mysql_fetch_array($rs);
    //if($year==$r["year"]){ $selected=' selected="selected"'; }//doesn't work so
    if (!in_array($r['year'], $tempholder)){
        $tempholder[$i] = $r['year'];
        echo "<option>".$r["year"]."</option>";//<option$selected>...
    }
}
unset($tempholder);
echo '</select>';

Answer 1

You must define $selected everytime, and you were using the assignment operator instead of the comparison:

echo '<select>';
$tempholder = array();
$rs = mysql_query("SELECT * FROM id ORDER BY year");
$nr = mysql_num_rows($rs);
for ($i = 0; $i < $nr; $i++){
    if($year == $r["year"]) { //not $year = $r["year"]
        $selected=' selected="selected"';
    }
    else {
       $selected = "";
    }
    $r = mysql_fetch_array($rs);
    if (!in_array($r['year'], $tempholder)){
        $tempholder[$i] = $r['year'];
        echo "<option$selected>" . $r["year"] . "</option>";
    }
}
unset($tempholder);
echo '</select>';

Answer 2

Try this one:

    echo '<select>';
$tempholder = array();
$rs = mysql_query("SELECT * FROM id ORDER BY year");
$nr = mysql_num_rows($rs);
for ($i=0; $i<$nr; $i++){
    $r = mysql_fetch_array($rs);
    if (!in_array($r['year'], $tempholder)){
        $tempholder[$i] = $r['year'];
        echo "<option".(($year==$r["year"])? ' selected="selected"' : '').">".$r["year"]."</option>";
    }
}
unset($tempholder);
echo '</select>';

It doesn't saves the state in a variable which you have to overwrite.

And I think the real error was the single equal sign in $year=$r["year"] and not wihtin the rest of the code.

Answer 3

In addition to fixing the =/== gotcha, you can save yourself the array lookup and make the code simpler by asking the database to return each year only once in the query:

<select>
    <?php $result= mysql_query('SELECT DISTINCT year FROM id ORDER BY year'); ?>
    <?php while($row= mysql_fetch_assoc($result)) { ?>
        <option <?php if ($row['year']==$year) { ?>selected="selected"<?php } ?>>
            <?php echo htmlspecialchars($row['year']); ?>
        </option>
    <?php } ?>
</select>

(You may not need htmlspecialchars() assuming that's a numeric year, but it's good practice always to HTML-escape any plain text you include in an HTML template. You can define a function with a shorter name to do the echo htmlspecialchars to cut down on typing. )