保持选择来自数据库的选择框值？

Question

i hope you can help i have got this query in a select box who listed all countrys out from database. i checked some solutions from similar questions but its didn't worked for me. how would i do this to keep the selected country selected after page refresh?

<select name="themecat[]" class="ui-widget" id="cb1">
<option value=choose a country>choose a country</option>
 <?php
 include_once("php_includes/db_conx.php");
 $sql = "SELECT countrys FROM countrylist";
 $query = mysqli_query($db_conx, $sql);
while ($row = mysqli_fetch_array($query))
{
echo "<option value='{$row['countrys']}'>{$row['countrys']}</option>";
}
?>
</select>

Answer 1

This depends on what you mean by "refresh".

If you are literally refreshing ie, F5, then you could use Javascript to store the value of the select in a session and on load if the session variable is set, set the select tag to selected.

If you want to only do it if the page is "POST", you can check in php if the page has been posted by checking the _POST varaible and setting the selected attribute accordingly.

See here on an example of how to set the selected option in PHP.

Display stored value from mysql table into select input field