PHP如何从用于创建菜单选项的For循环中获取值

Question

I'm trying to make a form I've created sticky.

I used a for loop to create some lengthy select options, but it can't seem to figure out a way to make it sticky.

Here is one of the loops I've created:

    <p>Ave. Speed: <select name="speed" id="speed">
    <option value="">Speed</option>
    <?php //Print out speed
    for ($s = 70; $s <=105; $s++) {
    print "<option value=\"$s\">$s
    </option>
";
    }
    ?>
    </select></p>

How can i do this ?

Answer 1

A couple of assumptions here, i.e. you are using POST to send your form data and no processing has been done on $_POST['speed'] yet. Check whether the value of $_POST['speed'] posted matches the value of $s and then use selected in your option tag:

<p>Ave. Speed: <select name="speed" id="speed">
<option value="">Speed</option>
<?php
//Print out speed
for ($s = 70; $s <=105; $s++) {
echo "<option value=\"$s\"";
if($_POST['speed']==$s){echo' selected="selected"';}
echo">$s</option>
";
}
?>
</select></p>