Creating a javascript alert with php that has a php variable inside?

Display variable php in alert javascript

   <?php 
          function died($error) { ?>

            <script>alert("<?php echo $error; ?>")</script>

    <?php   die(); 
          } ?>

You only forgot quotations that are required for the JavaScript alert.

If you passed 'hello' to the function, your current code would create alert as:

alert(hello)

instead of doing:

alert("hello")

Therefore, change your line to the following (two double quotes are added before and after concatenating $error):

echo '<script type="text/javascript">alert("'.$error.'");</script>';

and you can use your function:

died('error on whatever');

You can use function follow this:

function died($error) {
    echo '<script> alert("'.$error.'")</script>';
    die();
}