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  • python列表(list)

    #str  #类,字符串
    #name = "raitorei" #创建一个对象
    
    #list #类,列表
    ##############list类中提供的方法(灰魔法)##################
    # 对象.方法(..) ,li对象调用append方法
    # li = [1,2,3,4]
    # 1在原来值最后追加
    # li.append(5)
    # li.append([11,22])
    # li.append("raito")
    # print(li)
    
    # 2.清空列表
    # li.clear()
    # print(li)
    
    # 3.拷贝,浅拷贝
    # v = li.copy()
    # print(v)
    
    # 4.计算元素出现的次数
    # v = li.count(2)
    # print(v)
    
    # 5.扩展愿列表
    # li = [1,2,3,4,5]
    # li.append([4645,"fdafafd"])#[1, 2, 3, 4, 5, [4645, 'fdafafd']]
    # li.extend([4645,"fdafafd"])#[1, 2, 3, 4, 5, 4645, 'fdafafd']
    # li.extend("风动旛动")       #[1, 2, 3, 4, 5, '风', '动', '旛', '动']
    # print(li)
    
    # 6.根据值获取改值索引位置,左边有限
    # li = [1,2,3,4,5,2]
    # v = li.index(2)
    # print(v)
    
    # 7.在指定位置插入元素
    # li = [1,2,3,4,5]
    # li.insert(0,99)
    # print(li)
    
    # 8.删除某个值并获取当前的值(默认最后一个,可以指定索引)
    # li = [1,2,3,4,5]
    # v = li.pop()
    # v = li.pop(1)
    # print(li)
    # print(v)
    
    # 9.删除列表中指定的值,左边优先
    # li = [1,2,3,4,5]
    # li.remove(2)
    # print(li)
    # ps: pop,remove,del,li[0],del li[7:9],clear
    
    # 10.讲列表翻转
    # li = [1,2,3,4,5]
    # li.reverse()
    # print(li)
    
    # 11.排序
    # li = [1,2,3,4,5]
    # # li.sort()
    # li.sort(reverse=True)
    # print(li)
    
    
    ###############深灰魔法####################
    # 1.列表格式:中括号括起来,英文逗号分割每个元素,
    #            列表中的元素可以使数字,字符串,列表,布尔值
    #            集合内部可以防止任何东西
    # li = [1,2,"tsukirei",["轰",["Carole","Tuesday"],"绿谷"],"凌江"]
    # 2.索引取值
    # print(li[2])
    # 3.切片取值,切片结果也是列表
    # print(li[2:5])
    # 4.for循环取值
    # for i in li:
    #     print(i)
    # li = [1,2,"tsukirei",["轰",["Carole","Tuesday"],"绿谷"],"凌江"]
    # 5.索引修改
    # li[1] = 120
    # print(li)
    # li[1] = [1,2,3,4]
    # print(li)
    # 6.切片修改
    # li[0:1] = [10,20]
    # print(li)
    # 7.删除
    # del li[1]
    # print(li)
    # 8.是否存在某值
    # li = [1,2,"tsukirei",["轰",["Carole","Tuesday"],"绿谷"],"凌江"]
    # v = 1 in li
    # print(v)
    # 9.索引嵌套取值
    # li = [1,2,9,"tsukirei",["轰",["Carole",[12,13],"Tuesday"],"绿谷"],"凌江"]
    # print(li[4][1][1][0])
    # 10.转换(字符串可以转列表,数字不能直接转列表)
    # s = "qavapkhvakfjdkdf"
    # li = list(s)
    # print(li)
    # s = 123
    # li = list(str(s))
    # print(li)
    # 11.列表转字符串
    # li = [1,2,3,"123","raito"]
    # r = str(li)
    # print(r)    #[1, 2, 3, '123', 'raito']
    # 如果有数字和字符串只能自己循环
    # s = ""
    # for i in li:
    #     s += str(i)
    # print(s)
    # 如果只有字符串,可以用下面的方法
    # li = ["123","raito"]
    # v = "".join(li)
    # print(v)
    
    #补充:字符串创建不可以修改
    # li = [1,2,3,4]
    # print(li[0])
    # li[0] = 546
    # print(li)
    s = "raitorei"
    print(s[0])
    s[0] = "e"  #报错
    print(s)
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  • 原文地址:https://www.cnblogs.com/raitorei/p/11621047.html
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