Selenium是一个开源的和便携式的自动化软件测试工具，用于测试Web应用程序有能力在不同的浏览器和操作系统运行。Selenium真的不是一个单一的工具，而是一套工具，帮助测试者更有效地基于Web的应用程序的自动化。
有时候我们会碰到<select></select>标签的下拉框。直接点击下拉框中的选项不一定可行。Selenium专门提供了Select类来处理下拉框。
<select id="status" onchange="" name="status"><option value=""></option><option value="0">未审核</option><option value="1">初审通过</option><option value="2">复审通过</option><option value="3">审核不通过</option></select>
Python-selenium中的操作
先以python为例，查看Selenium代码select.py文件的实现：
.../selenium/webdriver/support/select.py
class Select:
def __init__(self, webelement):"""Constructor. A check is made that the given element is, indeed, a SELECT tag. If it is not,then an UnexpectedTagNameException is thrown.:Args:- webelement - element SELECT element to wrapExample:from selenium.webdriver.support.ui import Select /nSelect(driver.find_element_by_tag_name("select")).select_by_index(2)"""if webelement.tag_name.lower() != "select":raise UnexpectedTagNameException("Select only works on <select> elements, not on <%s>" % webelement.tag_name)self._el = webelementmulti = self._el.get_attribute("multiple")self.is_multiple = multi and multi != "false" 查看Select类的实现需要一个元素的定位。并且Example中给了例句。
Select(driver.find_element_by_tag_name("select")).select_by_index(2)def select_by_index(self, index):"""Select the option at the given index. This is done by examing the "index" attribute of anelement, and not merely by counting.:Args:- index - The option at this index will be selected """match = str(index)matched = Falsefor opt in self.options:if opt.get_attribute("index") == match:self._setSelected(opt)if not self.is_multiple:returnmatched = Trueif not matched:raise NoSuchElementException("Could not locate element with index %d" % index) 继续查看select_by_index() 方法的使用并符合上面的给出的下拉框的要求，因为它要求下拉框的选项必须要有index属性，例如index=”1”。
def select_by_value(self, value):"""Select all options that have a value matching the argument. That is, when given "foo" thiswould select an option like:<option value="foo">Bar</option>:Args:- value - The value to match against"""css = "option[value =%s]" % self._escapeString(value)opts = self._el.find_elements(By.CSS_SELECTOR, css)matched = Falsefor opt in opts:self._setSelected(opt)if not self.is_multiple:returnmatched = Trueif not matched:raise NoSuchElementException("Cannot locate option with value: %s" % value) 继续查看select_by_value() 方法符合我们的要求，它用于选取<option>标签的value值。最终，可以通过下面有实现选择下拉框的选项。
from selenium.webdriver.support.select import Select
……
sel = driver.find_element_by_xpath("//select[@id='status']")
Select(sel).select_by_value('0') #未审核
Select(sel).select_by_value('1') #初审通过
Select(sel).select_by_value('2') #复审通过
Select(sel).select_by_value('3') #审核不通过
Java-selenium中的操作
当然，在java中的用法也类似，唯一不区别在语法层面有。
package com.jase.base;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.By.ById;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.support.ui.Select;
public class SelectTest {
public static void main(String[] args){
WebDriver driver = new ChromeDriver();
driver.get("http://www.you_url.com");
// ……
Select sel = new Select(driver.findElement(ById.xpath("//select[@id='status']")));
sel.selectByValue("0"); //未审核
sel.selectByValue("1"); //初审通过
sel.selectByValue("2"); //复审通过
sel.selectByValue("3"); //审核不通过
}
}