简单如果其他声明。

Question

试图让它发挥作用..我不理解If else声明。基本上，如果Field Photo有一个值，我希望它显示的值如果它的值为Null显然是Else Statement woudl显示。

$row = photo

$id = $_GET['id'];
$sql = "SELECT * FROM menu_category WHERE id  = '$id' order by sort";
$query = mysql_query($sql);
while($row = mysql_fetch_array($query)) {

echo " <h1>".$row['category_field']."</h1> ";
echo "<div class=\"itemdescription\">  ".$row['description']."</div> ";

$row = photo("*");

if ($photo = "*") {
echo "Have a good day!";
} else {
echo "Have a good night!";
}

Answer 1

使用！空来检查照片是否存在，而不是*

   $row = photo

$id = $_GET['id'];
$sql = "SELECT * FROM menu_category WHERE id  = '$id' order by sort";
$query = mysql_query($sql);
while($row = mysql_fetch_assoc($query)) {
$photo_exist = $row['photo'];

echo " <h1>".$row['category_field']."</h1> ";
echo "<div class=\"itemdescription\">  ".$row['description']."</div> ";



if (!empty($photo_exist)) {
echo "Have a good day!";
} else {
echo "Have a good night!";
}