PHP remeber checked checkboxes - php

Question

I am trying to have a filter using checkboxes. Problem is when I unselect some boxes
and submit values, all boxes are selected again. I think the problem can be here
if (isset($_POST['option_meno']))
What can be the problem?
And yes Im new here, so any ideas hot to make my code simpler would help me also.
Thank you.
<?php
// Make a MySQL Connection
$query_o_meno = "SELECT meno FROM uctovnictvo GROUP BY meno ORDER BY meno";
$result_meno = mysql_query($query_o_meno) or die(mysql_error());
?>
<form method="post">
<?php
if (isset($_POST['Filtrovat'])) {
// Print checked checkboxes
echo "<strong>Meno:</strong>";
echo "<br />";
while($row = mysql_fetch_array($result_meno)){
//I believe the problem is line below -----------------------------
if (isset($_POST['option_meno'])) {
echo "<input type='checkbox' name='option_meno[]' value='".$row['meno']."' checked />" . $row['meno'];
echo "<br />";
//}
}
else{
echo "<input type='checkbox' name='option_meno[]' value='".$row['meno']."' / >" . $row['meno'];
echo "<br />";
}
}
}
else{
$option_meno = array();
echo "<strong>Meno:</strong>";
echo "<br />";
while($row = mysql_fetch_array($result_meno)){
echo "<input type='checkbox' name='option_meno[]' value='".$row['meno']."' checked />" . $row['meno'];
echo "<br />";
$option_meno[] = $row['meno'];
}
}
?>
<input type="submit" name="Filtrovat" value="Filtrovat" />
</form>

Answer 1

This is not tested, but should work:
if (isset($_POST['Filtrovat']))
{
// Print checked checkboxes
echo "<strong>Meno:</strong>";
echo "<br />";
while($row = mysql_fetch_array($result_meno))
{
$checked = "";
if(isset($_POST['option_meno']))
$checked = in_array($row['meno'],$_POST['option_meno'])?"
checked = 'checked' ":"";
echo "<input type='checkbox' name='option_meno[]'
value='".$row['meno']."' $checked / >" . $row['meno'];
echo "<br />";
}
}

Answer 2

Since you're doing name='option_meno[]', $_POST['option_meno'] will be an array. That array will always be set as long as at least one checkbox is checked. Try something like this:
<?php
// Make a MySQL Connection
$query_o_meno = "SELECT meno FROM uctovnictvo GROUP BY meno ORDER BY meno";
$result_meno = mysql_query($query_o_meno) or die(mysql_error());
?>
<form method="post">
<?php
if (isset($_POST['Filtrovat'])) {
// Print checked checkboxes
echo "<strong>Meno:</strong>";
echo "<br />";
while($row = mysql_fetch_array($result_meno)){
//I believe the problem is line below -----------------------------
if (isset($_POST['option_meno'][$row['meno']])) {
echo "<input type='checkbox' name='option_meno[".$row['meno']."]' value='".$row['meno']."' checked='checked' />" . $row['meno'];
echo "<br />";
//}
}
else{
echo "<input type='checkbox' name='option_meno[".$row['meno']."]' value='".$row['meno']."' / >" . $row['meno'];
echo "<br />";
}
}
}
else{
$option_meno = array();
echo "<strong>Meno:</strong>";
echo "<br />";
while($row = mysql_fetch_array($result_meno)){
echo "<input type='checkbox' name='option_meno[".$row['meno']."]' value='".$row['meno']."' checked />" . $row['meno'];
echo "<br />";
$option_meno[] = $row['meno'];
}
}
?>
<input type="submit" name="Filtrovat" value="Filtrovat" />
</form>
This way you check for each checkbox individually.
Note: You should always fully declare the checked attribute, like so: checked='checked'