[TOC] >[success] # list--列表 ~~~ 1.列表是python中的基础数据类型之一,其他语言中也有类似于列表的数据类型,比如js中叫数组,他是以[]括起来,每个元素以逗号隔开 列表相比于字符串,不仅可以储存不同的数据类型,而且可以储存大量数据,32位python的限制是 536870912 个元 素,64位python的限制是 1152921504606846975 个元素。而且列表是有序的,有索引值,可切片,方便取值。 2.列表也可以切片,对于切片理解可以看切片单独章节 ~~~ >[danger] ##### 创建列表 ~~~ test_list = ["周","吴","郑","王"] name_lists =list("周吴郑王") print(test_list) print(name_lists) 打印结果: ['周', '吴', '郑', '王'] ['周', '吴', '郑', '王'] ~~~ >[danger] ##### append/ += -- 在列表末尾添加 ~~~ 1.使用+= 时注意,如果直接字符串添加,会将字符串拆解,推荐列表添加例 2.append 添加不会将可迭代对象拆开,也就是如果是列表或者字符串之类的会把一个整体保存进去 3.+=/ ~~~ ~~~ test_list = ["周","吴","郑","王"] test_list.append("添加内容") print(test_list) test_list = ["周","吴","郑","王"] test_list += ['添加内容'] print(test_list) test_list = ["周","吴","郑","王"] test_list += '添加内容' print(test_list) 打印结果: ['周', '吴', '郑', '王', '添加内容'] ['周', '吴', '郑', '王', '添加内容'] ['周', '吴', '郑', '王', '添', '加', '内', '容'] ~~~ >[danger] ##### insert -- 添加到指定位置 ~~~ test_list = ["周","吴","郑","王"] test_list.insert(2,'insert') print(test_list) 打印结果: ['周', '吴', 'insert', '郑', '王'] ~~~ >[danger] ##### extend -- 添加可迭代对象 ~~~ test_list = ["周","吴","郑","王"] test_list.extend(['n','s']) print(test_list) 打印结果: ['周', '吴', '郑', '王', 'n', 's'] ~~~ >[danger] ##### pop -- 根据位置删除列表元素 ~~~ # 不填位置参数默认删除最后一个 test_list = ["周","吴","郑","王"] test_list.pop() print(test_list) # 填写参数大于数组长度,会报错 test_list = ["周","吴","郑","王"] test_list.pop(1) print(test_list) 打印结果: ['周', '吴', '郑'] ['周', '郑', '王'] ~~~ >[danger] ##### remove -- 指定内容删除 ~~~ # 不填和填写不存在都会报错 test_list = ["周","吴","郑","王"] test_list.remove("周") print(test_list) 打印结果: ['吴', '郑', '王'] ~~~ >[danger] ##### clear -- 清空列表中的内容 ~~~ test_list = ["周","吴","郑","王"] test_list.clear() print(test_list) 打印机结果: [] ~~~ >[danger] ##### del -- 删除列表 ~~~ test_list = ["周","吴","郑","王"] del test_list ~~~ >[danger] ##### 切片/角标 -- 指定替换列表中内容 ~~~ # 把切片指定内容去掉,把赋值内容进行迭代加入 test_list = ["周","吴","郑","王"] test_list[0:3] = ["w","s"] print(test_list) 打印结果: ['w', 's', '王'] test_list = ["周","吴","郑","王"] test_list[0] = ["w","s"] print(test_list) 打印结果: [['w', 's'], '吴', '郑', '王'] ~~~ >[danger] ##### index -- 查询特定值所在的位置 ~~~ # 想查询列表中某个值的位置时用index()列 name_list = ["周","吴","郑","王"] print(name_list.index("王")) 打印结果: 3 ~~~ >[danger] ##### in -- 判断值是否存在 ~~~ # 判断某个值是否存在列表中用in例: name_list = ["周","吴","郑","王"] print("王" in name_list) 打印结果 True ~~~ >[danger] ##### count -- 判断记录值出现的次数 ~~~ # 当想判断列表中,一个值出现的次数的时候count例: name_list = ["周","周","吴","郑","王"] print(name_list.count("周")) 打印结果 2 ~~~ >[danger] ##### join -- 将列表转换成字符串 ~~~ # 我们想把列表中的内容,整理成字符串输出可以使用join例: name_list = ["周","周","吴","郑","王"] print(",".join(name_list)) 打印结果: 周,周,吴,郑,王 ~~~ >[danger] ##### sort -- 重新排列元素 ~~~ # 当我们想吧列表中的元素,默认按照升序排列sort()列: num_list = [5,7,3,6,2,9,4] num_list.sort() print(num_list) 打印结果: [2, 3, 4, 5, 6, 7, 9] 降序排列可以使用num_list.sort(reverse=True),当然python也自带方法可以用来排序sorted(),其中sort不带返回值,sorted()带返回值 ~~~ >[danger] ##### len -- 获取长度 ~~~ # len -- 用来返回字符串,元组,列表等长度的例: A = "ssss" print(len(A)) 打印结果: 4 ~~~ >[danger] ##### reverse -- 反转 ~~~ name_list = ["周","吴","郑","王"] name_list.reverse() print(name_list) 打印结果: ['王', '郑', '吴', '周'] ~~~