str类型笔记
1 # 居中 第二个参数空白处用*填充 2 a1 = "alex" 3 ret = a1.center(20,'*') 4 print(ret) 5 6 # 计算a出现了几次 第二个参数是计算范围 7 a1 = "alex is alph" 8 ret = a1.count("al") 9 ret = a1.count('al',0,5) 10 print(ret) 11 12 # 判断以什么字符结尾 13 temp = "hello" 14 # 获取大于等于0的位置,小余2的位置 15 print(temp.endswith('e',0,2)) 16 17 #转换table为空格 18 content = "hello\t999" 19 print(content) 20 21 print(content.expandtabs()) 22 23 # 查找 如果找到了返回找到的位置,没找到返回-1 24 s = "alex hello" 25 print(s.find("ex")) 26 27 # 字符串格式化 28 s = "hello {0}, age {1}" 29 print(s) 30 # # {0} 是占位符 31 new1 = s.format("alex", 19) 32 print(new1) 33 34 # 查找 如果找到了返回找到的位置,没找到报错 35 s = "alex hello" 36 print(s.index("ex")) 37 38 # 连接 39 li = ["alex","eric"] 40 # 元祖也可以 41 li = ("alex","eric") 42 ret = "_".join(li) 43 print(ret) 44 45 #分割 前中后 三部分,以元组为单位 46 s = "alex SB eric" 47 print(s.partition('SB')) 48 49 #替换 50 s = "alex SB alex" 51 print(s.replace("al","BB",1)) 52 53 # 从右往左找 54 s = "alex SB alex" 55 print(s.rfind("SB")) 56 57 # 分割 58 s = "alexalex" 59 print(s.split("e")) 60 61 #根据换行符进行分割 62 s = "alex\nalex" 63 print(s.split("\n")) 64 65 #判断某个字符是否是某个字符串开始 66 s = "alexalex" 67 print(s.startswith("al")) 68 69 # 大写变小写,小写变大写 70 s = "AlExalEX" 71 print(s.swapcase()) 72 73 # 把字符串变成标题 74 s = "AlExalEX" 75 print(s.title()) 76 # 把字符串变成大写 77 s = "AlExalEX" 78 print(s.upper())