将jscolor从一个php页面传递到另一个

Question

I'm using jscolor and trying to pass the users selected color from test1.php to test2.php and then convert to rgb. Somehow is not working.

If I change the form post to test1.php it retrieves the correct value, but when changing action="test2.php" then is not working.

test1.php:

<script>
function update(jscolor) {
    // 'jscolor' instance can be used as a string
    document.getElementById('rect').style.backgroundColor = '#' + jscolor
}
</script>

 <form action="test2.php" method="post">
     Select you favorite color:
     <input name="clr1" class="jscolor {onFineChange:'update(this)'}">
     <input type="submit" name="submit">
 </form>
 <p id="rect" style="border:1px solid gray; width:161px; height:100px;">

<?php 
  session_start();

  if(isset($_POST['clr1'])) { 
      $selected_color = $_POST['clr1']; 
      $_SESSION['bgcolors'] = $selected_color;
  }
?>

test2.php:

session_start();
$selected_color = $_SESSION['bgcolors'];
echo $selected_color;
echo "<br>";
list($r, $g, $b) = array_map('hexdec', str_split($selected_color, 2));

$bgcolor2 = $r . "," . $g . "," .$b;
echo $bgcolor2;

Answer 1

Add in test2.php after session_start this code

 if (isset($_POST['clr1'])) { 
    $selected_color = $_POST['clr1']; 
    $_SESSION['bgcolors'] = $selected_color;
 }

Answer 2

In php page 2 you are going to want to retrieve the variable by starting the session with session_start and after that you can access it with $_SESSION['bgcolors']

However I can see a problem with your code in that you are not calling session_start the first think you do.

Always call session_start unconditionally. Always call session_start before you output anything on the page.

As seen in this stack response What is proper way to calling session_start()