处理Exec_Shell脚本时显示加载图像

I need to create a loader div with an image while script.sh is loading

Here's my code:

<?php
    if (isset($_POST['restartserver']))
    {
         shell_exec("my-script.sh");         
    }    
?>

<html>
<body>
<div class="refresh">
<form method="post">
    <p>
        <button class="button" name="restartserver">Restart Server</button>
    </p>
</form>
</div>
</body>
</html>   

So when i click on the button i need a loading image , when the script.sh is loaded the image-loader disapper and you can click again the button in the div.

Actually when i click on the button the script runs correctly but i see that the browser is loading the script, when finished it reload the same page.

I just want a loder image.gif when the script is loading

I know that this can be done with Ajax but i didn't find a working example

Use jQuery for easy ajax. Following code assumes the restart script outputs "complete" when the reboot is done, and anything else for an error.

$('#loaderdiv').html('<img src="loader.gif" />');

$.get('http://path.to/restart.php', function(data){
    if (data == "complete"){
       $('#loaderdiv').html('Reboot Complete');
    } else {
       $('#loaderdiv').html('An Error Has Occured');
    }

});

HTML

<div id="container">
    <button id="runscript">Run Script</button>
</div>

Javascript

$(document).ready(function(){

  $('#runscript').click(function(e){
      e.preventDefault();

      $('#container').html('<img src="loader.gif" />');

      $.get('http://path.to/execute_sh_script.php', function(data){
            // Code here executes once ajax is complete
            $('#container').html('**strong text**');
      });

  });

});