webdriver如何操作select

需要测试的网页用firefox查看如下

<formid="searchForm"enctype="application/x-www-form-urlencoded"action="/receive/asnList.xhtml"method="post"name="searchForm">

<inputtype="hidden"value="searchForm"name="searchForm">

<tablewidth="100%">

<tbody>

<tr>

<td>

<td>

<inputtype="text"style="width:118px"onblur="return ValidTextAreaLength(this,'30');"maxlength="30"name="searchForm.:j_id232">

</td>

<td>

<td>

<selectstyle="width:118px"size="1"name="searchForm.:j_id236">

<optionselected="selected"value="">-请选择-</option>

<optionvalue="1">1</option>

<optionvalue="2">2</option>

<optionvalue="3">3</option>

</select>

</td>

如果需要点击select控件，选择其中某个菜单，然后点击查询按钮，代码如下
Select asnselect=new Select(driver.findElement(By.xpath("//form[@id='searchForm' and @name='searchForm']/table/tbody/tr/td[4]/select")));
asnselect.selectByIndex(1);
driver.findElement(By.id("searchForm.:btnQuery")).click();