<a href="#addFriend" rel="faceBox" title="[+] add <?PHP echo $showU["full_name"]; ?> as friend">
    <div class="addFriend"></div></A>

<div id="addFriend" style="display:none; margin: auto;">
    <form action="javascript:DoFriendRequest()" method="post">
        <input name="commentFriend" type="text" id="commentFriend" value="" size="22"> 
        <input name="submit" type="submit" id="submit" value="Send">
    </form>
</div>

我的形式当它在这个元素里面是一个jquery灯箱，字段#commentFriend在DoFriendRequest中获取空值

function DoFriendRequest() {
    var wrapperId = '#insert_svar';
    $.ajax({ 
        type: "POST",url: "misc/AddFriendRequest.PHP",data: {
            mode: 'ajax',comment : $('#commentFriend').val() 
        },success: function(msg) {
            $(wrapperId).prepend(msg);
            $('#commentFriend').val("");
        }
    });
}

更新答案

但是当我删除显示：none，它是有效的。我该如何解决？