在Python中清除列表的不同方法

有很多方法可以通过Python语言提供的不同构造的方法来清除列表。让我们尝试一一了解每种方法。

• 方法 #1：使用clear()方法

  # Python program to clear a list
  # using clear() method 
    
  # Creating list
  GEEK = [6, 0, 4, 1]
  print('GEEK before clear:', GEEK) 
    
  # Clearing list 
  GEEK.clear() 
  print('GEEK after clear:', GEEK) 
  

  输出：

  GEEK before clear: [6, 0, 4, 1]
  GEEK after clear: []
  

• 方法#2：重新初始化列表：在该范围内初始化列表，初始化没有值的列表。即大小为 0 的列表。让我们看看演示方法 1 和 2 以清除列表的示例

  # Python3 code to demonstrate 
  # clearing a list using
  # clear and Reinitializing 
    
  # Initializing lists
  list1 = [1, 2, 3]
  list2 = [5, 6, 7]
    
  # Printing list1 before deleting 
  print ("List1 before deleting is : " 
  +  str(list1))
    
  # deleting list using clear()
  list1.clear()
    
  # Printing list1 after clearing
  print ("List1 after clearing using clear() : " 
  + str(list1))
    
  # Printing list2 before deleting 
  print ("List2 before deleting is : "
   +  str(list2))
    
  # deleting list using reinitialization
  list2 = []
    
  # Printing list2 after reinitialization
  print ("List2 after clearing using reinitialization : " 
  + str(list2))
  

  输出：

  List1 before deleting is : [1, 2, 3]
  List1 after clearing using clear() : []
  List2 before deleting is : [5, 6, 7]
  List2 after clearing using reinitialization : []
  

• 方法#3：使用“*= 0” ：这是一种鲜为人知的方法，但这种方法会删除列表中的所有元素并使其为空。

  # Python3 code to demonstrate 
  # clearing a list using
  # *= 0 method
    
  # Initializing lists
  list1 = [1, 2, 3]
    
  # Printing list1 before deleting 
  print ("List1 before deleting is : " + str(list1))
    
  # deleting list using *= 0
  list1 *= 0
    
  # Printing list1 after *= 0
  print ("List1 after clearing using *= 0: " + str(list1))
  

  输出：

  List1 before deleting is : [1, 2, 3]
  List1 after clearing using *= 0: []

• 方法#4 :使用del : del可用于清除范围内的列表元素，如果我们不给出范围，则删除所有元素。

  # Python3 code to demonstrate 
  # clearing a list using
  # del method
    
  # Initializing lists
  list1 = [1, 2, 3]
  list2 = [5, 6, 7]
    
  # Printing list1 before deleting 
  print ("List1 before deleting is : " + str(list1))
    
  # deleting list1 using del
  del list1[:]
  print ("List1 after clearing using del : " + str(list1))
    
    
  # Printing list2 before deleting 
  print ("List2 before deleting is : " + str(list2))
    
  # deleting list using del
  del list2[:]
  print ("List2 after clearing using del : " + str(list2))
  

  输出：

  List1 before deleting is : [1, 2, 3]
  List1 after clearing using del : []
  List2 before deleting is : [5, 6, 7]
  List2 after clearing using del : []