selenium不能启动firefox浏览器，怎么办？

一、Java（环境：eclipse Oxygen + JDK1.8 + selenium3.8.1 +Junit5 + firefox58.0_64位 + geckodriver V1.09.1_64位）

1.报错信息如下

The path to the driver executable must be set by the webdriver.gecko.driver system property; 
for more information, see https://github.com/mozilla/geckodriver. The latest version can be downloaded from https://github.com/mozilla/geckodriver/releases

java.lang.IllegalStateException: The path to the driver executable must be set by the webdriver.gecko.driver system property; for more information, see https://github.com/mozilla/geckodriver. The latest version can be downloaded from https://github.com/mozilla/geckodriver/releases
    at com.google.common.base.Preconditions.checkState(Preconditions.java:754)
    at org.openqa.selenium.remote.service.DriverService.findExecutable(DriverService.java:124)
    at org.openqa.selenium.firefox.GeckoDriverService.access$100(GeckoDriverService.java:41)
    at org.openqa.selenium.firefox.GeckoDriverService$Builder.findDefaultExecutable(GeckoDriverService.java:141)
    at org.openqa.selenium.remote.service.DriverService$Builder.build(DriverService.java:339)
    at org.openqa.selenium.firefox.FirefoxDriver.toExecutor(FirefoxDriver.java:158)
    at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:120)
    at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:98)
…………

部分源码如下：

      @Test
      public void setUp() throws Exception {
          
        try {

            driver = new FirefoxDriver();
            driver.get("https://www.baidu.com/");
            System.out.print(driver.getTitle());
            driver.quit();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
      }

2.解决方法如下：

　根据报错提示意为，缺少驱动。

　（1）根据提示链接：https://github.com/mozilla/geckodriver/releases

　下载最新驱动

（2）解压下载文件，把解压后的文件放入firefox.exe的同目录，默认为 C:Program Files (x86)Mozilla Firefox（此处最好配置环境变量path和PATH，这样就不用加上geckdriver的路径了）

（3）在源码中的加入

System.setProperty("webdriver.firefox.marionette",
                     "C:\Program Files (x86)\Mozilla Firefox\geckodriver.exe")；
如下：

      @Test
      public void setUp() throws Exception {
          
        try {
            System.setProperty("webdriver.firefox.marionette",
 6                     "C:\Program Files (x86)\Mozilla Firefox\geckodriver.exe");
            driver = new FirefoxDriver();
            driver.get("https://www.baidu.com/");
            System.out.print(driver.getTitle());
            driver.quit();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
      }

二、python（环境：python3.6.2 + pycharm2017,3,1 + selenium3.8.1 + geckodriver V1.09.0_64位 + firefox58.0_64位）

 1.报错信息如下：

selenium.common.exceptions.WebDriverException: Message: Unable to find a matching set of capabilities
提示报错行：driver = webdriver.Firefox()

此种情况表示火狐驱动有问题

2.解决方法如下

（1）验证驱动有没有放在firefox路径下，并在PATH和path下配置环境变量（举例：C:Program Files (x86)Mozilla Firefox）

　（2）保证火狐浏览器的版本和驱动的版本要一致，geckodriver V1.09.0+firefox58.0都必须是同样的版本（同64或同32）

 源代码如下

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
# 导入webdriver包
from selenium import webdriver
from time import sleep

driver = webdriver.Firefox()
driver.get("https://www.baidu.com/")
driver.find_element_by_xpath("//input[@id='kw']").send_keys("selenium")
driver.find_element_by_xpath("//input[@id='su']").click()
sleep(5)
driver.quit()

 （3）成功运行界面