异常值的处理:try & 爬虫初识

---------------------------异常值处理-------------------------

异常值处理：防止程序奔溃

• #常见的用法
  try:   
      val = input('请输入数字：')
      num = int(val)
  except Exception as e: #固定格式
      print('操作异常') #如果程序报错，执行如下内容
          
  # 也可用于函数        
  def func(a):
      try:
          a.strip()
      except Exception as e:
          print('处理失败')
      return 123
  v  = func([11,22,33])
  print(v)
      
  

• #爬虫的应用
  import requests
  def func1(url_list):
      result = []
      for url in url_list:
          try:
              response = requests.get(url)
              result.append(response.text)
          except Exception as e:
              pass
          return result
   func1(['http://www.baidu.com','http://www.google.com'])