类型错误By.css(tagName)

Question

我似乎不知道是什么导致了typeError，或者是为什么。基本上，我所要做的就是获取当前选定帧的名称。下面是代码和错误。

this.getCurrentFrameName = function(driver)
{
    var frames = driver.findElements(driver.By.css('frame'));
    for (var frame in frames)
    {
        if (frame.isSelected()) {
            return frame.getName;
        }
    }
};

错误

TypeError: Cannot read property 'css' of undefined
at getCurrentFrameName (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\src\FrameHandler.js:21:75)
at Context.<anonymous> (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\test\FrameHandlerTest.js:17:29)
at callFn (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runnable.js:315:21)
at Test.Runnable.run (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runnable.js:308:7)
at Runner.runTest (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runner.js:422:10)
at C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runner.js:533:12
at next (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runner.js:342:14)
at C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runner.js:352:7
at next (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runner.js:284:14)
at Immediate._onImmediate (C:\Users\charles.sexton\WebstormProjects\JS-Selenium-Toolkit\node_modules\mocha\lib\runner.js:320:5)

编辑：，我想将测试中的所有内容都包括在内，但是我仍然得到了与以前相同的错误。我没有包括期望值、断言或应该声明。

var expect = require('chai').expect;
var FrameHandler = require('../../JS-Selenium-Toolkit/src/FrameHandler.js');

var webdriver = require('selenium-webdriver');
/** required imports for Google Chrome without setting the PATH environment variable */
var chrome = require('selenium-webdriver/chrome');
var chromePath = require('selenium-chromedriver').path;

describe('FrameHandler', function()
{
var frameHandler = new FrameHandler();

it('', function()
{
    var service = new chrome.ServiceBuilder(chromePath).build();
    chrome.setDefaultService(service);

    var driver = new webdriver.Builder()
        .withCapabilities(webdriver.Capabilities.chrome())
        .build();

    driver.get('http://google.com');

    var frames = driver.findElements(driver.By.css('frame'));
    console.log(frames.length());
    for (var frame in frames)
    {
        console.log(frame.getName);
        if (frame.isSelected()) {
            console.log(frame.getName);
            return frame.getName;
        }
    }
});

})；

Answer 1

正如@amitbobade刚刚观察到的那样，By不是构造的构建器对象driver的属性，而是selenium-webdriver实例webdriver的属性。

(对于任何Java阅读器来说，这相当于尝试在WebDriver实例上调用WebDriver，而不是WebDriver类。)

所以使用webdriver.By，而不是driver.By。

您可以使用console.log看到不同之处。如果在webdriver上这样做，您可以看到以下内容：

webdriver =  { ActionSequence: [Function: ActionSequence],
  Browser: 
   { ANDROID: 'android',
     CHROME: 'chrome',
     [...]
     HTMLUNIT: 'htmlunit' },
  Builder: [Function: Builder],
  Button: { LEFT: 0, MIDDLE: 1, RIGHT: 2 },
  By: 
   [Function: name(name) {
       return By.css('*[name="' + escapeCss(name) + '"]');
     }],
  Capabilities: [Function: Capabilities],
  Capability: 
   { ACCEPT_SSL_CERTS: 'acceptSslCerts',
   [...]