Execute the reminder first and then jump? Or jump to a transition page, and then jump to the target page after the reminder?

Check whether SESSION exists before each jump. If it does not exist, jump. After the jump is successful, write SESSION.

$noticed = $_SESSION['noticed'];
if(isset($noticed)){
    //your code here
}

php can get the connection to the source page:

$_SERVER[“HTTP_REFERER”]

You can get the link to the source page and compare it to see if it jumps from the page you executed. to make a judgment. Or you can append a parameter to the jump connection after successful execution. When there are parameters, it prompts that the execution is successful. There is no reminder for normal refresh.

But it is more recommended that you write a function. Enter the prompt and the page to jump to. For details, please refer to the tips of some frameworks.

Based on the suggestions from the above people:

//跳转调用
function redirect($url,$message=false)
{
  if($message){
    foreach ($message as $key => $value) {
      if(is_array($value)){
        $_SESSION['RedirectMessage'][$key] = implode(',', urlencode($value));
      }else{
        $_SESSION['RedirectMessage'][$key] = urlencode($value);
      }
    }
  }
  header('location:'.$url);
}

//视图调用（在视图加判断）
function getMessage($key1)
{
  $data = explode(',',$_SESSION['RedirectMessage'][$key1]);
  $_SESSION['RedirectMessage'] = null;
  if(empty($data)){
    return false;
  }
  foreach ($data as $key => $value) {
    $data[$key] = urldecode($value);
  }
  if(count($data)==1){
    return $data[0];
  }else{
    return $data;
  }
}
/**
 * 参数是否存在
 */
function existsParam($key)
{
  if(isset($_SESSION['RedirectMessage'][$key])){
    return true;
  }else{
    return false;
  }
}