[Python知识库]python - 列表list

列表的常规使用

初始化

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

def test() -> None:
    my_list: list = [1, 2, 3, "zhangSan", [3, 5]]
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5]]
 
if __name__ == '__main__':
    test()

查询

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

def test() -> None:
    my_list: list = [1, 2, 3, "zhangSan", [3, 5]]
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5]]
    print(type(my_list))  # <class 'list'>

    # 查询
    print(type(my_list[0]), my_list[0])  # <class 'int'> 1
    print(type(my_list[4][1]), my_list[4][1])  # <class 'int'> 5

    # for遍历
    for i in range(len(my_list)):
        if type(my_list[i]) is list:
            for j in range(len(my_list[i])):
                print(my_list[i][j])
        else:
            print(my_list[i])

    # 截取
    print(type(my_list[1:2]), my_list[1:2])  # <class 'list'> [2]

    # 是否包含某个元素
    print("zhangSan" in my_list)  # True


if __name__ == '__main__':
    test()

修改

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

def test() -> None:
    my_list: list = [1, 2, 3, "zhangSan", [3, 5]]
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5]]
    print(type(my_list))  # <class 'list'>

    my_list[0] = 100
    print(my_list)  # [100, 2, 3, 'zhangSan', [3, 5]]

if __name__ == '__main__':
    test()

添加

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

def test() -> None:
    my_list: list = [1, 2, 3, "zhangSan", [3, 5]]
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5]]
    print(type(my_list))  # <class 'list'>

    # 追加
    my_list.append(100)
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5], 100]

    # 追加
    list.append(my_list, "address")
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5], 100, 'address']

    # 插入
    my_list.insert(0, 200)
    print(my_list)  # [200, 1, 2, 3, 'zhangSan', [3, 5], 100, 'address']

    # 插入列表
    my_list.insert(0, ["hello", "python"])
    print(my_list)  # [['hello', 'python'], 200, 1, 2, 3, 'zhangSan', [3, 5], 100, 'address']

    # 合并
    my_list.extend([1, 2, 3, 1000, 2000, 3000])
    print(my_list)  # [['hello', 'python'], 200, 1, 2, 3, 'zhangSan', [3, 5], 100, 'address', 1, 2, 3, 1000, 2000, 3000]
    
if __name__ == '__main__':
    test()

删除

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

def test() -> None:
    my_list: list = [1, 2, 3, "zhangSan", [3, 5]]
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5]]
    print(type(my_list))  # <class 'list'>

    # pop 默认删除最后一个，可以指定索引，返回该元素的值
    res = my_list.pop(3)
    print(res)  # zhangSan
    print(my_list)  # [1, 2, 3, [3, 5]]

    # remove 从前往后进行匹配，删除第一个匹配到的值
    my_list = [100, 200, 300, 100, 500]
    my_list.remove(100)
    print(my_list)  # [200, 300, 100, 500]

if __name__ == '__main__':
    test()

排序 、 反转

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

def test() -> None:
    my_list: list = [100, 200, 300, 100, 500]

    # 排序
    my_list.sort()
    print(my_list)  # [100, 100, 200, 300, 500]

    # 排序 反转
    my_list.sort(reverse=True)
    print(my_list)  # [500, 300, 200, 100, 100]

    # 反转
    print(my_list)  # [500, 300, 200, 100, 100]
    my_list.reverse()
    print(my_list)  # [100, 100, 200, 300, 500]

if __name__ == '__main__':
    test()

获取长度

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

def test() -> None:
    my_list: list = [1, 2, 3, "zhangSan", [3, 5]]
    print(my_list)  # [1, 2, 3, 'zhangSan', [3, 5]]
    print(type(my_list))  # <class 'list'>

    print(len(my_list))  # 5

if __name__ == '__main__':
    test()