如果放置了preventdefault，Jquery将不会POST

Question

I want to make a form where you write a number send it with Jquery and is shown by PHP without refreshing the page ,by far i have this code but if preventDefault() is placed it will post but the content is not shown,also if i remove it, the content is shown but the page will pe refreshed.

Javascript:

$('#testut').unbind('submit').bind('submit',function(ev) {
    ev.preventDefault();
    $.ajax({
        type: 'post',
        url: 'incerc.php',
        data: $('form').serialize(),
        success: function () {
            $('.success').fadeIn(500);
        }
    });
});
}

HTML:

Test
<br />
<?php
if(isset($_POST['test'])) {
    $test = $_POST['test'];
    $numar = $_POST['numar'];
    echo 'Order name:'.$test.'<br />Number:'.$numar.'<br />';
} else {
    echo 'No <br />';
}
?>
<div id='testut'>
    <form id='test' method='post'>
        <input type='text' name='numar'><br />
        <input type='submit' name='test' onclick ='check()' value='Place'><br />
        <span class='success' style='display:none'>Order was successfully placed.</span>
    </form>
</div>

Answer 1

I wanted to execute a query after the POST in php,the example was just for test, so i managed to do this(on example).

Javascript:

function check(){
$("#test").submit(function(e)
{   var numar = $('#numar').val();
    var test = $('#testim').val();
    var dataString = 'numar='+ numar + '&test=' + test;

    $.ajax(
    {
        url : 'incerc.php',
        type: "POST",
        data : dataString,
        success:function(data, textStatus, jqXHR) 
        {
            $('.success').fadeIn(500);
            $('body').load('incerc.php?'+dataString);
        },
        error: function(jqXHR, textStatus, errorThrown) 
        {
            $('.success').html("Nu a mers");     
        }
    });
    e.preventDefault(); 
    e.unbind(); 
});

}

HTML:

<?php if(isset($_GET['test'])){
$test = $_GET['numar'];
$numar = $_GET['numar'];
echo 'Order name:'.$test.'<br />Number:'.$numar.'<br />';}
else{echo 'No <br />';} ?>
<div id='testut'>
<form name='test' id='test' method='POST'>
<input type='text' id='numar' name='numar'><br />
<input type='submit' id='testim' name='test' onclick ='check()' value='Place'><br />
<span class='success' style='display:none'>Order was successfully placed.</span>
</form>

So now the body will load when the data is sent sucessfully , and will get the result correctly ,also in the adress bar it will still show 'incerc.php' not 'incerc.php?'+dataString.