my login form execute only in chrome. it doeasn't work in IE and firefox. it understand that this is the correct username but it doesn't redirect to the page. I use ajax and joomla. this is my code:

<script>
function Send()
{
jQuery.post("index.php?option=com_market&view=login&format=raw",
    {Username:jQuery("#username").val(),Pass:jQuery("#password").val()},
    function(data)
    {
        jQuery("#loginValid").html(data);
    }); 

}

</script>

<form name="loginForm" id="loginForm" method="post">
<label>Username:</label><input type="text" name="username" id="username"  /><br />
<label>Password:</label><input type="password" name="password" id="password" /><br />
<input type="button" onclick="Send();" value="login" name="loginSubmit" id="login"  />
</form>

the code of page in address: index.php?option=com_market&view=login&format=raw

<?php
session_start();
if(isset($_POST['Username'])) {
    $Username=$_POST['Username'];
    $db = JFactory::getDBO();
    $pass = md5($_POST['Pass']);
    $query ="select id from sb5qt_market_users where username='$Username' and     password='$pass'";
    $db->setQuery($query);
    $db->query();
    $rows = $db->getNumRows();
    $result = $db->loadResult();

    if ($rows == 0) {
        echo "invalid username or password";
    } else {
        $_SESSION['id']=$result;
        echo  '<META http-equiv="refresh" content="0;URL=http://example.com/profile">';
    }
}
?>

Seems to me like an odd way of redirecting and I'm not really surprised browsers are having trouble with it.

You could try this:

in PHP

if($rows == 0)
{
   echo json_encode(array("error" => "invalid username or password", "redirect" => ""));
}
else
{
   $_SESSION['id']=$result;
   echo json_encode(array("error" => "", "redirect" => "http://example.com/profile"));
}

Then in your Javascript something like...

jQuery.ajax({
    url: 'index.php?option=com_market&view=login&format=raw',
    data: 'Username=' + jQuery("#username").val() + "&Pass=" + jQuery("#password").val(),
    type: 'post',
    dataType: 'json',
    success: function(data)
    {
       if (data['error']) {
         jQuery("#loginValid").html(data['error']);
       }

       if (data['redirect']) {
         location.href = data['redirect'];
       }
   }
});

I haven't tested any of that but you can see what I'm getting at...

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