如何使用Python Selenium在文本框（输入）中定位和插入值？

我具有以下HTML结构，并且尝试使用Selenium输入值NUM：

<div class="MY_HEADING_A">
    <div class="TitleA">My title</div>
    <div class="Foobar"></div>
        <div class="PageFrame" area="W">                
             <span class="PageText">PAGE <input id="a1" type="txt" NUM="" />  of <span id="MAX"></span> </span>
</div>

这是我编写的代码：

head = driver.find_element_by_class_name("MY_HEADING_A")
frame_elem = head.find_element_by_class_name("PageText")

# Following is a pseudo code. 
# Basically I need to enter a value of 1, 2, 3 etc in the textbox field (NUM) 
# and then hit RETURN key.
## txt  = frame_elem.find_element_by_name("NUM")
## txt.send_keys(Key.4"

如何获取此元素并输入值？

假设您的页面在“ http://example.com ”下可用

from selenium import webdriver
from selenium.webdriver.common.keys import Keys

driver = webdriver.Firefox()
driver.get("http://example.com")

按ID选择元素：

inputElement = driver.find_element_by_id("a1")
inputElement.send_keys('1')

现在您可以模拟击回车键：

inputElement.send_keys(Keys.ENTER)

或者，如果您是一种表格，您可以提交：

inputElement.submit()