求助用Jquery实现，点击添加选项新增一行

求助用Jquery实现，点击添加选项新增一行，点击后增加选项五，再点击增加选项六

<table id="table_items" class="hovertable" style="width: 100%;" cellspacing="0"
    cellpadding="0">
    <tr id="tr">
        <td class="table_th" >题目选项：
        <td width="" id="contain"><input type="text" id="comment" name="comment"
            maxlength="30" style="width: 80%"  placeholder="选项一"/><font
            color="red"> *</font>
                <input type="text" id="title" name="title"
            maxlength="30" style="width: 80%"" placeholder="选项二" />
                <input type="text" id="commentx" name="comment"
            maxlength="30" style="width: 80% " " placeholder="选项三" />
                        <input type="text" id="commentx" name="comment"
            maxlength="30" style="width: 80% "  placeholder="选项四" />

            <div><a href="javascript:;" class="addRow" id="addText" onclick="javascript:add()">+添加选项</a></div>

            </td>
    </tr>
    </table>

 <script>
    function del(t){
         $(t).parent('div').remove();
    }
    function add(){
         var lastInput = $('#contain input:last');
         var phName = lastInput.attr('placeholder');
         phName = phName.replace("选项","");
         if(phName=='一'){
              phName='二'
         }else if(phName=='二'){
              phName='三'
         }else if(phName=='三'){
              phName='四'
         }else if(phName=='四'){
              phName='五'
         }else if(phName=='五'){
              phName='六'
         }
         $('<div class="inputs"><input input type="text" id="commentx" name="comment" maxlength="30" style="width: 80% "  placeholder="选项'+phName+'" /><span onclick=del(this)>删除</span></div>').insertAfter(lastInput.parent('div'));
    }
</script>
<body> 
    <table id="table_items" class="hovertable" style="width: 100%;" cellspacing="0"
    cellpadding="0">
    <tr id="tr">
        <td class="table_th" >题目选项：        
        <td width="" id="contain">
              <div class='inputs'>
              <input type="text" id="comment" name="comment"
            maxlength="30" style="width: 80%"  placeholder="选项一"/><font
          color="red"> *<span  onclick=del(this)>删除</span></font></div>

              <div class='inputs'><input type="text" id="title" name="title"
            maxlength="30" style="width: 80%"" placeholder="选项二" /><span  onclick=del(this)>删除</span></div>

              <div class='inputs'><input type="text" id="commentx" name="comment"
            maxlength="30" style="width: 80% " " placeholder="选项三" /><span  onclick=del(this)>删除</span></div>

              <div class='inputs'><input type="text" id="commentx" name="comment"
            maxlength="30" style="width: 80% "  placeholder="选项四" /><span  onclick=del(this)>删除</span></div>

            <div><a href="javascript:;" class="addRow" id="addText" onclick="javascript:add()">+添加选项</a></div>

            </td>
    </tr>
    </table>
</body>

$("#table_items").append("

new row");

append 里传的是添加行的html代码

 function add(){
         var lastInput = $('#contain input:last');
         var phName = lastInput.attr('placeholder');
         phName = phName.replace("选项","");
         if(phName=='四'){
              phName='五'
         }else if(phName=='五'){
              phName='六'
         }
         $('<input input type="text" id="commentx" name="comment" maxlength="30" style="width: 80% "  placeholder="选项'+phName+'" />').insertAfter(lastInput);
    }

这个

参考:

function add(nums){
$("#contain").append(' maxlength="30" style="width: 80% " placeholder="选项'+nums+'" />');
}
大概这样就可以.

另外,id是不可以重复的。