如何在mysqli_fetch_array php中获取第一个值

Question

I have this code where am able to perfectly get all values from the database using php mysqli_fetch_array with while loop

    $pid = 1;                                             
    $sqlSI = "SELECT * FROM productcolor where proId='$pid'";
    $SIresult = mysqli_query($conn, $sqlSI);
        
    if (mysqli_num_rows($SIresult) == 1) {
        echo ' <h4>Color</h4>
        <div class="colors">';

        while ($row = mysqli_fetch_array($SIresult)) {
            ?>

        <a href="javascript:void(0)" class="s-colors" data-color="<?= $row['colors']; ?>" style="background-color: <?= $row['colors']; ?>;"></a>

        <script>
            $(document).ready(function () {
                $(".pdt-color-cart").val("<?= $row['colors']; ?>");
            })
        </script>

<?php
        }
        echo ' </div>';
    }
    else if (mysqli_num_rows($SIresult) > 1) {
        
        $rowed = mysqli_fetch_array($SIresult);
        echo $rowed['colors'];

        echo ' <h4>Color</h4>
        <div class="colors">';
        
        while ($row = mysqli_fetch_array($SIresult)) {
            
            ?>

        <a href="javascript:void(0)" class="s-colors" data-color="<?= $row['colors']; ?>" style="background-color: <?= $row['colors']; ?>;"></a>

<?php
        }
        echo ' </div>';
    } else {
        echo "";
    }
    

?>

In the code above I did one where if the value is 1 then do this else if it is more than 1 then still do this.

But what I want is that while it is doing the > 1 loop, I want to be able to still grab one value out of it - especially the first value that will come out.

How do you do it?

Answer 1

This task can be achieved easier if you tidy up your code a little bit. Instead of mixing the database logic with presentation logic, simply fetch the data before you start outputting your HTML/JavaScript. You can store the number of elements in a variable.

// Fetch the data and store it in an array
$stmt = $conn->prepare('SELECT * FROM productcolor where proId=?');
$stmt->bind_param('s', $pid);
$stmt->execute();
$data = $stmt->get_result()->fetch_all(MYSQLI_ASSOC);
$no_of_elements = count($data);

// If more than one element present in the results
if ($no_of_elements > 1) {
    echo $data[0]['colors'];
}

echo ' <h4>Color</h4>
<div class="colors">';
foreach ($data as $row) {
    echo <<<S_COLORS_BLOCK
    <a href="javascript:void(0)" class="s-colors" data-color="{$row['colors']}" style="background-color: {$row['colors']};"></a>
    S_COLORS_BLOCK;
}

// If only one element is present then display JavaScript
if ($no_of_elements === 1) {
    echo '
    <script>
        $(document).ready(function () {
            $(".pdt-color-cart").val('.json_encode($row['colors']).');
        })
    </script>';
}

Answer 2

If I understood you correctly, you want to "remember" what the first color that pops out is? In that case you could have a variable set before the first if, something like $saveColor = TRUE. Then inside the elseif, check $saveColor, if TRUE, change it to FALSE and also set a 2nd variable to save the color, like

$firstColorFound = $rowed['colors'];

or something like that.

Next time it loops, $saveColor won't be TRUE anymore, and thus $firstColorFound won't be overwritten. Hope that helped!