请问这个代码怎么解决问题

# coding=utf-8
import  os
from time import sleep
from selenium import webdriver

def browser_init(isWait):
    options = webdriver.EdgeOptions()
    prefs = {'profile.default_content_settings.popups': 0, 'download.default_directory': 'E:\\PycharmProjects\\downloadCNKI\\output'}
    options.add_experimental_option('prefs', prefs)
    browser = webdriver.Edge(executable_path='E:\\Python\\各类软件\\新建文件夹\\edgedriver_win64 (1)\\msedgedriver.exe', options=options)
    browser.set_window_size(500,500)
    if isWait:
        browser.implicitly_wait(50)
    return browser

def searchKey(keyword):
    browser.get("http://kns.cnki.net/kns/brief/default_result.aspx")
    browser.find_element_by_id('txt_1_value1').send_keys(keyword)
    browser.find_element_by_id('btnSearch').click()

def switchToFrame(browser):
    #print 'start switch'
    browser.switch_to.frame('iframeResult')
    #print 'end switch'

def getDownloadLinks(browser,paper_downloadLinks):
    for link in browser.find_elements_by_css_selector('a[href^=\/kns\/detail]'):
        #link.click()
        url=link.get_attribute('href')
        url_part = url.split('&')[3:6]
        url_str= '&'.join(url_part)
        down_url='http://kns.cnki.net/KCMS/detail/detail.aspx?'+url_str
        #print down_url
        paper_downloadLinks.append(down_url)

def switchToPage(browser,n):
    for link in browser.find_elements_by_css_selector('a[href^=\?curpage]'):
        url=link.get_attribute('href')
        print(url)
        pageInd='curpage=%d&'%n
        print(pageInd)
        if pageInd in url:
            print("page: "+url)
            link.click()
            break
def switchNextPage(browser):
    browser.find_element_by_link_text(u'下一页').click()

def do_download(driver,urls,fail_downLoadUrl):
    for url in urls:
        print(url)
        driver.get(url)
        paper_title=driver.title
        print("paper title"+paper_title)
        if u'中国专利全文数据库' in paper_title:
            continue
        print("try  download :"+paper_title)
        try:
            driver.find_element_by_xpath("//a[contains(text(),'PDF下载')]").click()
            print("download success!!!")
        except Exception as e:
            try:
                driver.find_element_by_xpath("//a[contains(text(),'整本下载')]").click()
                print("download success!!!")
            except Exception as e:
                print("download fail!!!")
                fail_downLoadUrl.append(url)

def usage():
    print("example : python downloadCNKI.py -k keyword  -p 1")

if __name__=="__main__":

    keyword=u'三角形'      #论文搜索的关键字
    pageNum = 1     # 下载多少页的论文

    browser=browser_init(True)
    searchKey(keyword)
    switchToFrame(browser)
    paper_downloadLinks = []    #论文下载链接

    curPage=1
    while curPage<=pageNum:
        getDownloadLinks(browser,paper_downloadLinks)

        switchNextPage(browser);
        curPage+=1
    browser.quit()
    print("采集了%d条数据"% len(paper_downloadLinks))
    driver=browser_init(False)
    fail_downLoadUrl=[]         #记录下失败的网站
    do_download(driver,paper_downloadLinks,fail_downLoadUrl)
    print(fail_downLoadUrl)
    tryNum=0
    #尝试N次重新下载没有下载的
    while tryNum<5:
        if len(fail_downLoadUrl) !=0:
            paper_downloadLinks=fail_downLoadUrl
            fail_downLoadUrl=[]
            do_download(driver, paper_downloadLinks, fail_downLoadUrl)
            print(fail_downLoadUrl)
        else:
            break
        tryNum+=1
    sleep(60)
    driver.quit()

你的代码问题是什么

selenium可以爬可见内容，但是知网不会轻易爬取到的，而且你也没登录，爬不到数据正常

爬知网，很有想法。知网，似乎登陆了也看不了里面的具体内容吧。