jquery怎么根据选择框动态设置输入框的id或name值

jquery如何根据选择框动态设置输入框的id或name值?
RT,

<tr>
     <td>
     <select id="moreinfo" name="moreinfo" style="width: 150px" onchange="selected()">
     <option id="MC" selected="selected">被执行人名称</option>
     <option id="FDDBR">法人代表</option>
     <option id="DZ">住所地址</option>
     </select>
     </td>
     </tr>
     <tr>
     <td>
     <input type="text" id="MC" name="MC">
     </td>
     </tr>


比如当我选择法人代表的时候,下面的输入框的id和name值全都改变为“FDDBR”,忘各位大神指点一二
------解决方案--------------------
<!DOCTYPE html>
<html>
    
    <head>
        <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js">
        </script>
        <script>
            $(document).ready(function() {
                $("#moreinfo").change(function(e) {
                    alert($(this).val());
                    if ($(this).val() == "法人代表") {
                        $("#MC").attr("name", "FDDBR");
                        $("#MC").attr("id", "FDDBR");
                        alert($(".FDDBR").val())

                    }
                });

            });
        </script>
    </head>
    
    <body>
        <tr>
            <td>
                <select id="moreinfo" name="moreinfo" style="width: 150px" onchange="selected()">
                    <option id="MC" selected="selected">
                        被执行人名称
                    </option>
                    <option id="FDDBR">
                        法人代表
                    </option>
                    <option id="DZ">
                        住所地址
                    </option>
                </select>
            </td>
        </tr>
        <tr>
            <td>
                <input type="text" id="MC" name="MC" class="FDDBR" value="test">
            </td>
        </tr>
    </body>

</html>