请教:怎么用javascript判断数组的元素是否为空?
<table width="100%" border="0" cellspacing="0" cellpadding="0"><tr>
<form name="appraise" action="blogappraise.php?article_id=<?php echo $rowfile[0][article_id]?>" method="POST" onsubmit="return check_app()">
<td align="center"><input type="radio" name="appraise[]" value="1" />1</td>
<td align="center"><input type="radio" name="appraise[]" value="2" />2</td>
<td align="center"><input type="radio" name="appraise[]" value="3" />3</td>
<td align="center"><input type="radio" name="appraise[]" value="4" />4</td>
<td align="center"><input type="radio" name="appraise[]" value="5" />5</td>
<td align="center"><input type="radio" name="appraise[]" value="6" />6</td>
<td align="center"><input type="radio" name="appraise[]" value="7" />7</td>
<td align="center"><input type="radio" name="appraise[]" value="8" />8</td>
<td align="center"><input type="radio" name="appraise[]" value="9" />9</td>
<td align="center"><input type="radio" name="appraise[]" value="10" />10</td>
<td align="center"><input type="submit" name="Submit" value="评 分"></td>
</form>
</tr>
</table>
请问如何判断上面生成数组的值为空?
先谢谢了!!!!