<div id="user_nickname" class="n_p_e">
<input type="text" name="user_nickname" placeholder="昵称"
maxlength="12">
</div>
var user_nickname = $("#user_nickname input").val(); 取不到值
<input type="text" name="user_nickname" placeholder="昵称"
maxlength="12">
</div>
var user_nickname = $("#user_nickname input").val(); 取不到值
