js获取表格的行数和列数的方法

<table width="100%" border="1" cellspacing="0" cellpadding="0" id="example_table">   <tr>     <td> </td>     <td> </td>     <td> </td>     <td> </td>     <td> </td>   </tr>   <tr>     <td> </td>     <td> </td>     <td> </td>     <td> </td>     <td> </td>   </tr>   <tr>     <td> </td>     <td> </td>     <td> </td>     <td> </td>     <td> </td>   </tr> </table> 

//表格行数 var rows = document.getElementById("example_table").rows.length;  //表格列数 var cells = document.getElementById("example_table").rows.item(0).cells.length;