3.4列表元素修改新增删除

发布时间 2023-07-06 10:39:21作者: 等风来lzd

列表修改值

animals =["老虎","狮子","豹子","长颈鹿","大象"]
print(animals)

animals[0] = "东北虎"
animals[2] = "猎豹"
print(animals)

输出结果如下:
['老虎','狮子','豹子','长颈鹿','大象']
['东北虎','狮子','猎豹','长颈鹿','大象']

 列表添加元素

方法一:通过list.append(element)方法,可以给列表末尾添加元素

append 附加

animals = ["老虎","狮子","豹子","长颈鹿","大象"]
print(animals)

animals.append("斑马")
animals.append("犀牛")
print(animals)

输出结果如下:
['老虎','狮子','豹子','长颈鹿','大象']
['老虎','狮子','豹子','长颈鹿','大象','斑马','犀牛']

 方法二:经常会这么用:初始化一个空列表,后面再添加值到列表;例如读取文件的过程;

animals = []
print(animals)

animals.append("斑马")
animals.append("犀牛")
print(animals)

输出结果如下:
[]
['斑马','犀牛']

  列表删除元素

通过list.remove(element)的语法,可以按值删除元素

remove 去除 去掉  element 元素

animals = ["老虎","狮子","豹子","长颈鹿","大象"]
print(animals)

animals.remove("狮子")
animals.remove("长颈鹿")
print(animals)


输出结果如下:
['老虎','狮子','豹子','长颈鹿','大象']
['老虎','豹子','大象']