我试图让我的程序获取发布的id并使用它来更新我的数据库中的其他字段,当我回显变量时它工作正常,但是如果我回显我的sql字符串它不在那里
<body class="container">
<form class="form-horizontal" method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
<div class="form-group">
<label for="amount"><?php echo $id; ?></label>
<input type="number" name ="amount" class="form-control" id="amount" placeholder="Hvað viltu hækka/lækka um marga kassa?">
</div>
<button type="submit" name="plus" class="btn btn-default"><i class="fa fa-plus" aria-hidden="true"></i></button>
<button type="submit" name="minus" class="btn btn-default"><i class="fa fa-minus" aria-hidden="true"></i></button>
</form>
</body>
php code
require_once("include/header.php");
require_once("include/mysqliConn.php");
$id = $_POST['number'];
$orginal = $_POST['magn'];
if(isset($_POST['plus'])){
$amount = $_POST['amount'];
$finalAmount = $orginal+$amount;
$sql = 'UPDATE stada SET Magn="'.$finalAmount.'", lastModified="Aron DC" WHERE Nr="'.$id.'"';
echo $sql;
if ($conn->query($sql) === TRUE) {
echo "New record created";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
$conn->close();
}
if(isset($_POST['minus'])){
if ($orginal>$amount) {
$amount = $_POST['amount'];
$finalAmount = $orginal-$amount;
$sql = 'UPDATE stada SET Magn="'.$finalAmount.'", lastModified="Aron DC" WHERE Nr="'.$id.'"';
if ($conn->query($sql) === TRUE) {
echo "New record created";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
$conn->close();
}else{
echo '<script>alert("Þú getur ekki tekið fleiri kassa en eru til á lager");</script>';
}
}
这是一张图片