我正在尝试下载验证码图像，每次加载页面时其 URL 和内容都会动态更改，我知道我可以为浏览器截取屏幕截图并找到验证码图像位置，但我无法找到验证码图片。
从 HTML 源代码中我发现了这个
//该脚本用于生成验证码
<iframe marginheight="0" marginwidth="0" scrolling="no" frameborder="0" width="203" height="53" name="Captcha" src="/efs/servlet/efs/jsp-ns/captcha.jsp"></iframe>
//当我点击 src="/efs/servlet/efs/jsp-ns/captcha.jsp"时，它会引导我到此
<html>
<head><meta scheme='a1afcc517bec909bf5c3fddea7c83c3d' name='TSd58639' content='b133d7457db43c81' /> <meta scheme='eb1e31097f37b3d64bef23cbd5cab231' name='1000' content='5' /><!-- 9cc5da25f89a21d1fbb5ffa18da0bb73 --><script type="text/javascript">//<![CDATA[
eval(function(a){var f=a.split("");var c=f.length;var b=parseInt(f[0]+f[1],16);var e=String.fromCharCode(b);for(var d=2;d<c;d++){var g=(parseInt(f[d]+f[d+1],16)-b)%256;b=g;e+=String.fromCharCode(g);d++}return e}("288..."));
</script>
<script language="JavaScript">var pn = "CSRT"; var pv = '3642466061891909727';
eval(function(a){var f=a.split("");var d=f.length;var c=parseInt(f[0]+f[1],16);var e=String.fromCharCode(c);for(var b=2;b<d;b++){var g=(parseInt(f[b]+f[b+1],16)-c)%256;c=g;e+=String.fromCharCode(g);b++}return e}("288edbe3..."));
</script>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<img src="Captcha.jpg?t=1378993130057" border=1/>
</body>
</html>
这一行'<img src="Captcha.jpg?t=1378993130057" border=1/>'定义验证码网址，但数字“t=1378993130057”动态更改
我看过这个帖子 Download image with selenium python 但我不明白作者如何找到图像位置，例如
img = browser.find_element_by_xpath('//*[@id="cryptogram"]')
对于谷歌验证码 [ http://www.google.com/recaptcha/demo/recaptcha]
img = driver.find_element_by_xpath('//div[@id="recaptcha_image"]/img')
更新
try:
browser.save_screenshot('screenshot.png')
img = browser.find_element_by_xpath('//body/img')
src = img.get_attribute('src')
loc = img.location
except Exception,e:
print e
输出
Message: u'Unable to locate element: {"method":"xpath","selector":"//body/img"}' ; Stacktrace:
at FirefoxDriver.prototype.findElementInternal_ (file:///tmp/tmppjlmPW/extensions/fxdriver@googlecode.com/components/driver_component.js:8899)
at FirefoxDriver.prototype.findElement (file:///tmp/tmppjlmPW/extensions/fxdriver@googlecode.com/components/driver_component.js:8908)
at DelayedCommand.prototype.executeInternal_/h (file:///tmp/tmppjlmPW/extensions/fxdriver@googlecode.com/components/command_processor.js:10840)
at DelayedCommand.prototype.executeInternal_ (file:///tmp/tmppjlmPW/extensions/fxdriver@googlecode.com/components/command_processor.js:10845)
at DelayedCommand.prototype.execute/< (file:///tmp/tmppjlmPW/extensions/fxdriver@googlecode.com/components/command_processor.js:10787)
更新#2
from selenium import webdriver
import datetime
from selenium.webdriver.common.proxy import *
print '[+] Starts at '+ datetime.datetime.now().isoformat()
browser = webdriver.Firefox()
browser.get("https://www.example.com")
try:
browser.save_screenshot('screenshot.png')
img = browser.find_element_by_xpath('//body/img')
src = img.get_attribute('src')
loc = img.location
except Exception,e:
print e
browser.delete_all_cookies()
browser.close()
print '[+] Done at ' + datetime.datetime.now().isoformat()
非常感谢任何帮助。
最佳答案
可以通过xpath获取img标签，获取src属性值，然后通过urlretrieve下载:
import urllib
img = browser.find_element_by_xpath('//body/img')
src = img.get_attribute("src")
urllib.urlretrieve(src, "captcha.png")
关于python - 无法在 Selenium 中找到元素，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/18766087/