selenium+java 定位方法 findElement 之 By css

通过css定位：css定位有N种写法，列几个常用写法:

id css:
driver.findElement(By.cssSelector("#kw") 
name css :
driver.findElement(By.cssSelector("[name=wd]") 
className css :
driver.findElement(By.cssSelector(".s_ipt") 
span css:
driver.findElement(By.cssSelector("span.soutu-btn> input#kw")
form css:
driver.findElement(By.cssSelector("form#form > span > input")