<table border="" cellspacing="0" cellpadding="1">
   <tr style="background-color: #0099cc;">
    <td><input type="checkbox"class="all"/></td>
    <td style="text-align: center; width: 200px;">商品</td>
    <td style="color: white; width: 70px; height: 30px; text-align: center;">價錢</td>
   </tr>
   <tr class="zuida">
    <td><input type="checkbox" class="lla"/></td>
    <td>蘋果</td>
    <td style="text-align: center;" class="zongji">8000</td>
   </tr>
   <tr  class="zuida">
    <td><input type="checkbox" class="lla"/></td>
    <td>香蕉</td>
    <td style="text-align: center;" class="zongji">5000</td>
   </tr>
   <tr  class="zuida">
    <td><input type="checkbox" class="lla"/></td>
    <td>梨子</td>
    <td style="text-align: center;" class="zongji">2000</td>
   </tr>
   <tr  class="zuida">
    <td><input type="checkbox" class="lla"/></td>
    <td>蔬菜</td>
    <td style="text-align: center;" class="zongji">2000</td>
   </tr>
   <tr>
    <td colspan="3">總價是：<span class="zongjia">0</span>元</td>
   </tr>
</table>

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      var num=0;
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       var xuanzhi=$(rom).find(".zongji").text()*1;
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