How to Show an Alert Box in PHP

How to show an alert box in PHP?

use this code

echo '<script language="javascript">';
echo 'alert("message successfully sent")';
echo '</script>';

The problem was:

you missed "
It should be alert not alery

How to pop an alert message box using PHP?

You could use Javascript:

// This is in the PHP file and sends a Javascript alert to the client
$message = "wrong answer";
echo "<script type='text/javascript'>alert('$message');</script>";

Show alert from php action page after fetching the records from the database

If you want to use an alert you need to set it in the success part of your ajax call.
See below:

$.ajax({ url: 'two.php',
             data: {var1: var1value} //Pass your variables here
             type: 'post',
             success: function(output) {  //This is where you receive the result from two.php
                  //Do whatever you want with the data stored in output
                  alert('It worked!'); //Alert whatever you need here           
             },
             error: function() {
                  alert('That did not work...'); //Handle errors here
             }
        });

In the success or error functions you can update other DOM elements in your page as well, which may be more elegant than just an alert.

showing alert box using php and javascript

Try window.location.href = '/index.html inside script

if (! (isset($_POST['fullname']) && strlen($_POST['fullname']))) {
    echo "<script type=\"text/javascript\">window.alert('You must enter your full name.');window.location.href = '/index.html';</script>"; 
   exit;
}

Next page by clicking OK on alert box

For achive this functionality you can do as below

echo "<script>if(confirm('Your Record Sucessfully Inserted. Now Login')){document.location.href='index.php'};</script>";

php alert box with ok and cancel buttons

Here's a quick example to get you started:

index.php

<?php
//....
$user =  "John Doe"; // $row['user_name'];
$message = "User $user is logged in. Do you want to take over?";

if (isset($_GET['takeover'])) {
    if ($_GET['takeover'] == "confirm") {
        // $stmt1 = $connect->pre......etc
        exit(json_encode(["message" => "Access confirmed"])); // Send response to JS
    } else {
        // $stmt1 = $connect->pre......etc
        exit(json_encode(["message" => "Access revoked"])); // Send response to JS
    }
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>TEST</title>
</head>
<body>

  <h1>MY USER INTERFACE</h1>

  <script>
    const takeover = confirm("<?= $message ?>");
    fetch(`?takeover=${takeover ? "confirm" : "revoke"}`)
      .then(response => response.json())
      .then(data => {
        console.log(data);
      });
  </script>
</body>
</html>

the server will "strip" PHP tags before serving the page, but the echoed values will remain. I.e: $message inside the JavaScript code.
On Document ready the confirm() triggers, and a boolean value is carried in JS.
Depending on that value simply fetch the same file (or any other if you want) using a GET request somepagename.php?takeover=confirm
Listen in PHP for $_GET requests and respond to the AJAX request with a JSON response.
Open console, and see the server respond with the adequate message object data.

Happy coding.

How do you display a JavaScript alert from PHP?

instead of:

echo "Data has been submitted to $to!";

just

echo '<script type="text/javascript">alert("Data has been submitted to ' . $to . '");</script>';

Alert message after submitting form in PHP

After long researching, I found solution to delay the alert message with jQuery delay() function, the delay allowing the HTML page load and then execute the alert.
Thanks to all who helped me to get to this result.

  <script>
      $(document).ready(function(){
          setTimeout(function() {
              <?php
              if( $_GET['status'] == 'success') {
                  echo 'alert("welldone");';
              }
              else{
                  echo 'alert("no good");';
              }
              ?>
              }, 500);
      });
  </script>

How to Show an Alert Box in PHP