PHP foreach doesn't select the dropdown list

Question

I have a this html:

<option value="yes">Yes</option>
<option value="no">No</option>

and my php:

<?php
exec('uci get sms_gateway.setting.filter',$filt);
echo '<form action='.$_SERVER['PHP_SELF'].' method="post">
<select name="filter">';
foreach ($filt as $value){

if ($filt = "yes"){
    echo '<option value="'.$value.'" selected>Yes</option><br>
          <option value="no">No</option><br>ini yes';}
else {
    echo '<option value="yes">Yes</option><br>
          <option value="'.$value.'" selected>No</option><br> ini no';
}
}
echo '
</select>
<input type="submit" name="submit" value="Submit">';
if(isset($_POST['submit'])){
    {
        $data = $_POST['filter'];
        echo "<br>halo ". $data;
    }
    }
?>

the $filt only has one string it's either yes or no when it's yes I want the yes part on the dropdown menu selected, but when it's no I want the no part on the dropdown selected. How should I do that?

Firstly, you're doing an assignment `if ($filt = "yes"){` rather than a comparison `if ($filt == "yes"){` — Funk Forty Niner, Feb 17 '15 at 17:04
I tried that, but it messed up my code, the output of `no` on the dropdown list becomes `yes` while it should stay `no` — Lin, Feb 17 '15 at 17:06
You need to pass your POST and set the variable for it, then compare. — Funk Forty Niner, Feb 17 '15 at 17:07
Can you please write the code? I'm sorry I'm still learning... — Lin, Feb 17 '15 at 17:09
`foreach ($filt as $value)` you're doing `as $value` so try `foreach ($filt as $value){ if ($value == "yes"){` — Funk Forty Niner, Feb 17 '15 at 17:13
Then you have 2 sets of braces `if(isset($_POST['submit'])){ { $data = $_POST['filter']; echo "
halo ". $data; } }` which should error out. — Funk Forty Niner, Feb 17 '15 at 17:20
You're welcome. I posted my answer below which you can mark as solved and also noticed a missing closing `` tag, which is also in my answer; just in case. — Funk Forty Niner, Feb 17 '15 at 17:40

Funk Forty Niner · Accepted Answer · 2015-02-17T17:36:39.137

This bit of code:

foreach ($filt as $value) you're doing as $value so use:

foreach ($filt as $value){
 if ($value == "yes"){

Then you have 2 sets of braces which are not needed; they're just extra keystrokes for nothing:

if(isset($_POST['submit'])){
    {
        $data = $_POST['filter'];
        echo "<br>halo ". $data;
    }
    }

Change it to:

if(isset($_POST['submit'])){
        $data = $_POST['filter'];
        echo "<br>halo ". $data;
    }

Another thing I spotted, a missing closing </form> tag.

Just for the record, you were also assigning using a single = sign, instead of comparing using two == for:

if ($filt = "yes")

which theoretically should have read as

if ($filt == "yes")

Add error reporting to the top of your file(s) which will help find errors.

<?php 
error_reporting(E_ALL);
ini_set('display_errors', 1);

// rest of your code

Sidenote: Error reporting should only be done in staging, and never production.

score 0 · Answer 2 · edited May 23 '17 at 10:09

There's many things wrong with your code, you're treating "$filt" as both an array and a value, you're also assigning (=) instead of comparing. I'll give you a working example instead of trying to fix your code:

<?php $possibleValues = array('yes', 'no'); // All possible options ?>
<?php $valueYouWantSelected = 'yes'; // 'yes' will be selected ?>

<select>

    <?php foreach ($possibleValues as $value): ?>

        <?php $selected = ($valueYouWantSelected == $value) ? 'selected' : null; // Select this option if it equals $valueYouWantSelected ?>

        <option value="<?php echo $value;?>" <?php echo $selected; ?>>
            <?php echo $value; ?>
        </option>

    <?php endforeach ?>

</select>

If you're confused about how I assign $selected, check out ternary operators.

Also, I'm using alternative syntax, it makes it easier to organize PHP code within HTML (and colors code properly in your editor).

PHP foreach doesn't select the dropdown list

2 Answers2