Create a new element by selenium dynamically

问题

What I need is to add a script tag to the head of html document. I am using the code below but when I view page source, the script is not there. Thank you in advance,

driver = webdriver.Chrome()
driver.get("http://www.x.org")


execu = '''
var scr = document.createElement('script');
scr.type = 'text/javascript';
scr.text = `let calls = (function(){
    let calls = 0;
    let fun = document.createElement;
    document.createElement = function(){
      calls++;
      return fun.apply(document, arguments);
    }
    return ()=>calls;
})();`
document.head.appendChild(scr);
'''
try:
    driver.execute_async_script(execu)
except Exception,e:
    print str(e)

回答1:

Absolutely you can add script tag into HEAD dynamically by selenium execute_script api, please try below simple code. if it work, you can change the scr.text to your content

driver = webdriver.Chrome()
driver.get("http://www.x.org")
// sleep 10 seconds wait page load complete
// you should change to wait in official script
time.sleep(10)

execu = '''
var scr = document.createElement('script');
scr.type = 'text/javascript';
scr.text = 'alert("yes")';
document.head.appendChild(scr);
'''
try:
    driver.execute_script(execu) // if it work, an alert with 'yes' should display

    // sleep for a long time, so that you have more time to 
    // check the script tag appended into head tag or not.
    // only for debug purpose
    time.sleep(30)

except Exception,e:
    print str(e)

Please execute below 4 lines one by one in DevTool's Console Tab:

If You can get an alert, an inserted script tag in HTML head, it means the javascript snippet worked fine on your browse, the failure should comes from other python code lines

来源：https://stackoverflow.com/questions/48861078/create-a-new-element-by-selenium-dynamically