validate表单验证
4.errorPlacement：Callback?Default:?把错误信息放在验证的元素后面
指明错误放置的位置，默认情况是：error.appendTo(element.parent());即把错误信息放在验证的元素后面
errorPlacement:?function(error,?element)?{??
????error.appendTo(element.parent());??
}
//示例：
<tr>
????<td?class="label"><label?id="lfirstname"?for="firstname">First?Name</label></td>
????<td?class="field"><input?id="firstname"?name="firstname"?type="text"?value=""?maxlength="100"?/></td>
????<td?class="status"></td>
</tr>
<tr>
????<td?style="padding-right:?5px;">
????????<input?id="dateformat_eu"?name="dateformat"?type="radio"?value="0"?/>
????????<label?id="ldateformat_eu"?for="dateformat_eu">14/02/07</label>
????</td>
????<td?style="padding-left:?5px;">
????????<input?id="dateformat_am"?name="dateformat"?type="radio"?value="1"?/>
????????<label?id="ldateformat_am"?for="dateformat_am">02/14/07</label>
????</td>
????<td></td>
</tr>
<tr>
????<td?class="label">?</td>
????<td?class="field"?colspan="2">
????????<div?id="termswrap">
????????????<input?id="terms"?type="checkbox"?name="terms"?/>
????????????<label?id="lterms"?for="terms">I?have?read?and?accept?the?Terms?of?Use.</label>
????????</div>
????</td>
</tr>
errorPlacement:?function(error,?element)?{
????if?(?element.is(":radio")?)
????????error.appendTo(?element.parent().next().next()?);
????else?if?(?element.is(":checkbox")?)
<span st