td里的值为空的情况下,table的线不显示怎么办

Question

td里的值为空的情况下,table的线不显示怎么办

Answer 1

代码忘记写了     
   <table border="1" cellpadding="1" 
 cellspacing="1" >
            <tr >
                <td style="width: 100px">
                    a</td>
                <td style="width: 100px">
                    a</td>
                <td style="width: 100px">
                    a</td>
            </tr>
            <tr >
                <td style="width: 100px; border-top-style: solid; border-right-style: solid; border-left-style: solid; border-bottom-style: solid;" >
                  </td>
                <td style="width: 100px">
                    a</td>
                <td style="width: 100px">
                    a</td>
            </tr>
            <tr >
                <td style="width: 100px">
                    a</td>
                <td style="width: 100px">
                    a</td>
                <td style="width: 100px">
                    </td>
            </tr>
        </table>

Answer 2

style="width: 100px; border-top-style: solid; border-right-style: solid; border-left-style: solid; border-bottom-style: solid;" 
取掉不就显示了吗
没太明白你什么意思

Answer 3

<td style="width: 100px" colspan=2>
直接合并了

Answer 4

或者里面再镶一个 一行一列的table border=1