刷新页面时，php UPDATE发送到MYSQL空参数

Question

此代码点击提交UPDATE用户邮箱和名称，但当我在浏览器中刷新页面时，此代码向MySQL发送一个空字符串，我的意思是在MySQL中刷新页面或浏览器列名称和电子邮件变空后，< / p>

   $con=mysqli_connect("localhost","root","","test");

// Check connection
if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

// escape variables for security
$name = mysqli_real_escape_string($con, $_POST['name']);
$email = mysqli_real_escape_string($con, $_POST['email']);
$userid=$ss['user']['id'];




$sql="UPDATE table_users SET name = '$name', email = '$email' WHERE user_id='$userid'     ";

if (!mysqli_query($con,$sql)) {
  die('Error: ' . mysqli_error($con));
}
echo "----1 record added";

mysqli_close

Answer 1

更改为

if(isset($_POST['username'])){
  if (!mysqli_query($con,$sql)) {
    die('Error: ' . mysqli_error($con));
  }
}

你没有检查post中的值是否设置。