循环数组问题

Question

I have a simplified ajay script, from which I have removed all nonrelevant code. The problem I am having is first with my columns array and the subsequent foreach loop. I want to go through each element and change the corresponding element to YES if true and NO if false, I don't see why it isn't working.

If there are any problems such as syntax errors or braces or such, they are a problem from simplifying my code, and are not present in the version on my machine.

<?php
$con = mysqli_connect("localhost", "", "", "");
if (!$con) {
    echo "Can't connect to MySQL Server. Errorcode: %s
". mysqli_connect_error();
    exit;
}
$con->set_charset("utf8");
    $query1 = 'SELECT EGGS, SALAD, TREES, REVISED FROM AUCTIONS WHERE ARTICLE_NO = ?';
    if ($getRecords = $con->prepare($query1)) {
        $getRecords->bind_param("s", $pk);
        $getRecords->execute();
        $getRecords->bind_result($EGGS, $SALAD, $TREES, $REVISED);
        while ($getRecords->fetch()) {
        $columns = array('EGGS', 'SALAD', 'TREES', 'REVISED');
            foreach($columns as $column) {
                $$column = $columns[$column] ? 'YES' : 'NO';
            }
            imageSize = imageResize($PIC_URL, 250, 300);
            echo "<h1>".$EGGS."</h1>";
        }
    }
function imageResize($imageURL, $maxWidth, $maxHeight) {
    $imageSize["width"] = 0;
    $imageSize["height"] = 0;
    $size = getimagesize($imageURL);
    if ($size) {
        $imageWidth  = $size[0];
        $imageHeight = $size[1];
        $wRatio = $imageWidth / $maxWidth;
        $hRatio = $imageHeight / $maxHeight;
        $maxRatio = max($wRatio, $hRatio);
        if ($maxRatio > 1) {
            $imageSize["width"] = $imageWidth / $maxRatio;
            $imageSize["height"] = $imageHeight / $maxRatio;
            return $imageSize;
        } else {
            $imageSize["width"] = $imageWidth;
            $imageSize["height"] = $imageHeight;
            return $imageSize;
        }
    } else {
        die(print_r(error_get_last()));
    }
}

Answer 1

Your loop is wrong - $columns['EGGS'] doesn't exist:

$columns = array('EGGS', 'SALAD', 'TREES', 'REVISED');
foreach($columns as $column) {
    $$column = $columns[$column] ? 'YES' : 'NO';
}

it should be:

$columns = array('EGGS', 'SALAD', 'TREES', 'REVISED');
foreach($columns as $column) {
    $$column = $$column ? 'YES' : 'NO';
}

or better still:

$tmp = array();
$columns = array('EGGS', 'SALAD', 'TREES', 'REVISED');
foreach($columns as $column) {
    $tmp[$column] = $$column ? 'YES' : 'NO';
}

so that you're not over-writing your bound variables.

also note that you should move that constant array declaration outside of your while() loop for performance reasons.