Aug. 2, 2020
字符串的索引与切片
取字符串某一位的字符 用中括号 [ ]。
注意: 字符串的第一个位置的编号是 “0”, 不是 “1”
但是 字符串如果从最后一位开始数的话, 最后一位的编号是 “-1”
举例:
str = "ABCDE"
print(str[0])
print(str[1])
print(str[2])
print(str[3])
print(str[4])
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.3&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9cmMfedByKfqaEPe5DHQ-xDObP2BwhRZJeZ19V_IO-mO_9qMjWZ4gXj6csQfD-LBV-oRv216M663IG1Coqt0e3SAP4IEIIjsBYUC_FwtGiqG_jBFlQEA3bBUw&disp=emb&realattid=ii_kddfl1i04)
还可以反方向取值:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.1&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ87eZNLVB4RtHRh9NLJP0GXoVAkMPVHqn03IzCa36LQkl6GNgVzJzUaIhJ2kr4rChekrGt-VXh6HjtIn-0OxhYzdSRBeS9phzSOLTo4KKgHNCaDWqbJxNyILmI&disp=emb&realattid=ii_kddffdpn2)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.2&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-nex2UIVews1zq9A0tFedp8DPS_NCF4AN5AvtunCJ1ZPUSnttxiU3Sv2MEuKTa8g9Ju7bn1ogF5b_22-MZppzaKVqedtH-_bGh-JbXnvOilgsyzA-eoIwdvJw&disp=emb&realattid=ii_kddffs6o3)
按切片取值:
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.4&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-5o06qJ57Vcbdjvate54Ewq3c0OCaQQIlU_fF22HSezo1yUtMEKtz1mGMfXuPTTx9QC7wuwrn2wD3g-kf8FOpqvEyjjPqE70Vis_lszLNmDnQ3HyK7R7viH1w&disp=emb&realattid=ii_kddfwib25)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.5&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9WW3q8G7FuwbnyocQ4TzPvTJC-SigM_9X5LGkicO8yKMm7z7oglB4A9q97NFsLMFsQrQwP4nZcSJQBzsTwOJyY0CUeOIzfGlqvTpzqaqd_biaD0cY-5gOS83w&disp=emb&realattid=ii_kddfx3p86)
注意切片时,
(1) 如果写成 “1:5" 的形式, 在第5位的字符时不包含在内的。
(2) 如果写成"0:5" 的形式,“0” 可以省略,写成" :5" 的形式。
注意:字符串的起始位 和终止位 的顺序 一定是 小的数 在前,大的数在后。比如 [1:5], [:5] , [-5:-1],[-5:]
如果写成这样就错了:[-1: -5] 程序输出为空,但是不报错.
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.6&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ8RsFxUMF00pnH-lnPFJqW2MHWflpZf1G1sjyOaRz3QBRPtCBjcqpyJYQEtVOpJ60Bv6yS4T9Rju-QIQu0SAsIiiVwE2LgcczaqVsbEJayyi9ubFirzDtxjy3E&disp=emb&realattid=ii_kddiugt47)
输出结果如下:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.7&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ8PaqMmpQIQ0HwGJaFHKoRobqzGi6O5r3eiotzwmkTFiPLgB-c_GwsE1aeJkgZbS4mKkg0Me9PJpxROI6wzm9PwB2XzxmJVAd4A7PRtqIv93T9iCXQ9KFal1mk&disp=emb&realattid=ii_kddiyc128)
如果想这样写的话,就必须写成str[-1:-5:-1]
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.9&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9e9cuxGeIwyL4CJWqUF2qdOXksdi9kVxKvR0Ew2VgQgD1UuAUzxnCaECWWNXj1g_WE0RURkqFLahywpzH1yowacP_lp9Cef91QW-uNoVFOwQYHLCScblwqw3I&disp=emb&realattid=ii_kddjk6h811)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.10&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-SWTiA0dXqjPhkYaChtu0ZlL1LcxHOiW8iX1x_Ymqw5sOzeH638MGR9dUtOE-IEMlTc9iZd0GEElkVJo8gFo3evrc8hXBuLAmHWGACmUVXBHoWloR-vOpAX0U&disp=emb&realattid=ii_kddjkq3712)
总结:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.8&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-HNm9Qcfpvh2WNKnlRbb96a0Up3Eu4ygLIWvXAU5jx641tp_5ehPuQPE_A_PS_2QYa7kC4i7IXeR8VO2mdyCyIIX1hzn_rtgYKus6YNhHOYngibOj5AXDMPHE&disp=emb&realattid=ii_kddjdh0o10)
字符串的常用方法:
1. 大小写转换:.upper() .lower()
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.11&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ_-wWooytiREwk_gWPi48vWIlKLU8QV-L_hW4wKye27IUBbPY-ytd2tzN3u35DYw5WIq8E1JZWiTxoyk-0AmN4GHca1I3WhG7FSepdAbRVlW5Stv-xeqtqRnAo&disp=emb&realattid=ii_kddjwong13)
输出结果:
.startswith .endswith:
用于判断一个字符串的起始位 和 终止位的 字符是否正确 。
输出结果是 true or False
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.13&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9KPHxkBbgJU00VpNYq00gXnZf8EM-PCcP_xQ0DFp1RmfzUd-cgzfWKjrmVG7WntBWLi-Gmb44uCRGHPwCl5BbeqgMXAQUCOUYJIX6binI1PUfdGV3ejlya-xc&disp=emb&realattid=ii_kddl1xdz15)
输出结果:
.replace:
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.15&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9YjbjR-3RfdOFXCmguFgTefQWM-qR3g_wETYRq2LAeij8VQpVn0jznmAls1ZPqO7zb_VCMl52ZQym7HTpZNSSP-agsQ8chqiNPMxMElq8NXpW375yvhEH6pPo&disp=emb&realattid=ii_kddlcgii17)
输出结果:
.strip()
去除空白 : 包括 : 空格,\t, \n
此命令只是去除 起始位和结束位 的空格,并不去除 字符串字符之间的空格或者换行符。
举例:
字符串的索引与切片
取字符串某一位的字符 用中括号 [ ]。
注意: 字符串的第一个位置的编号是 “0”, 不是 “1”
但是 字符串如果从最后一位开始数的话, 最后一位的编号是 “-1”
举例:
str = "ABCDE"
print(str[0])
print(str[1])
print(str[2])
print(str[3])
print(str[4])
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.3&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9cmMfedByKfqaEPe5DHQ-xDObP2BwhRZJeZ19V_IO-mO_9qMjWZ4gXj6csQfD-LBV-oRv216M663IG1Coqt0e3SAP4IEIIjsBYUC_FwtGiqG_jBFlQEA3bBUw&disp=emb&realattid=ii_kddfl1i04)
还可以反方向取值:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.1&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ87eZNLVB4RtHRh9NLJP0GXoVAkMPVHqn03IzCa36LQkl6GNgVzJzUaIhJ2kr4rChekrGt-VXh6HjtIn-0OxhYzdSRBeS9phzSOLTo4KKgHNCaDWqbJxNyILmI&disp=emb&realattid=ii_kddffdpn2)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.2&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-nex2UIVews1zq9A0tFedp8DPS_NCF4AN5AvtunCJ1ZPUSnttxiU3Sv2MEuKTa8g9Ju7bn1ogF5b_22-MZppzaKVqedtH-_bGh-JbXnvOilgsyzA-eoIwdvJw&disp=emb&realattid=ii_kddffs6o3)
按切片取值:
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.4&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-5o06qJ57Vcbdjvate54Ewq3c0OCaQQIlU_fF22HSezo1yUtMEKtz1mGMfXuPTTx9QC7wuwrn2wD3g-kf8FOpqvEyjjPqE70Vis_lszLNmDnQ3HyK7R7viH1w&disp=emb&realattid=ii_kddfwib25)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.5&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9WW3q8G7FuwbnyocQ4TzPvTJC-SigM_9X5LGkicO8yKMm7z7oglB4A9q97NFsLMFsQrQwP4nZcSJQBzsTwOJyY0CUeOIzfGlqvTpzqaqd_biaD0cY-5gOS83w&disp=emb&realattid=ii_kddfx3p86)
注意切片时,
(1) 如果写成 “1:5" 的形式, 在第5位的字符时不包含在内的。
(2) 如果写成"0:5" 的形式,“0” 可以省略,写成" :5" 的形式。
注意:字符串的起始位 和终止位 的顺序 一定是 小的数 在前,大的数在后。比如 [1:5], [:5] , [-5:-1],[-5:]
如果写成这样就错了:[-1: -5] 程序输出为空,但是不报错.
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.6&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ8RsFxUMF00pnH-lnPFJqW2MHWflpZf1G1sjyOaRz3QBRPtCBjcqpyJYQEtVOpJ60Bv6yS4T9Rju-QIQu0SAsIiiVwE2LgcczaqVsbEJayyi9ubFirzDtxjy3E&disp=emb&realattid=ii_kddiugt47)
输出结果如下:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.7&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ8PaqMmpQIQ0HwGJaFHKoRobqzGi6O5r3eiotzwmkTFiPLgB-c_GwsE1aeJkgZbS4mKkg0Me9PJpxROI6wzm9PwB2XzxmJVAd4A7PRtqIv93T9iCXQ9KFal1mk&disp=emb&realattid=ii_kddiyc128)
如果想这样写的话,就必须写成str[-1:-5:-1]
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.9&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9e9cuxGeIwyL4CJWqUF2qdOXksdi9kVxKvR0Ew2VgQgD1UuAUzxnCaECWWNXj1g_WE0RURkqFLahywpzH1yowacP_lp9Cef91QW-uNoVFOwQYHLCScblwqw3I&disp=emb&realattid=ii_kddjk6h811)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.10&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-SWTiA0dXqjPhkYaChtu0ZlL1LcxHOiW8iX1x_Ymqw5sOzeH638MGR9dUtOE-IEMlTc9iZd0GEElkVJo8gFo3evrc8hXBuLAmHWGACmUVXBHoWloR-vOpAX0U&disp=emb&realattid=ii_kddjkq3712)
总结:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.8&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ-HNm9Qcfpvh2WNKnlRbb96a0Up3Eu4ygLIWvXAU5jx641tp_5ehPuQPE_A_PS_2QYa7kC4i7IXeR8VO2mdyCyIIX1hzn_rtgYKus6YNhHOYngibOj5AXDMPHE&disp=emb&realattid=ii_kddjdh0o10)
字符串的常用方法:
1. 大小写转换:.upper() .lower()
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.11&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ_-wWooytiREwk_gWPi48vWIlKLU8QV-L_hW4wKye27IUBbPY-ytd2tzN3u35DYw5WIq8E1JZWiTxoyk-0AmN4GHca1I3WhG7FSepdAbRVlW5Stv-xeqtqRnAo&disp=emb&realattid=ii_kddjwong13)
输出结果:
.startswith .endswith:
用于判断一个字符串的起始位 和 终止位的 字符是否正确 。
输出结果是 true or False
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.13&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9KPHxkBbgJU00VpNYq00gXnZf8EM-PCcP_xQ0DFp1RmfzUd-cgzfWKjrmVG7WntBWLi-Gmb44uCRGHPwCl5BbeqgMXAQUCOUYJIX6binI1PUfdGV3ejlya-xc&disp=emb&realattid=ii_kddl1xdz15)
输出结果:
.replace:
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.15&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9YjbjR-3RfdOFXCmguFgTefQWM-qR3g_wETYRq2LAeij8VQpVn0jznmAls1ZPqO7zb_VCMl52ZQym7HTpZNSSP-agsQ8chqiNPMxMElq8NXpW375yvhEH6pPo&disp=emb&realattid=ii_kddlcgii17)
输出结果:
.strip()
去除空白 : 包括 : 空格,\t, \n
此命令只是去除 起始位和结束位 的空格,并不去除 字符串字符之间的空格或者换行符。
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.17&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ85AAf2ERQPBczrx8MCs_EGYcsc8tF_9QLj0fQcHse6ilFN5BdjJ8q9pvB_BAwPjL8s6luB348pUrinHN_sCK0muU1vtssTqViblZP8o_LgCAJeAybvdT3Lxak&disp=emb&realattid=ii_kddm2fuz20)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.18&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9eqodILUR2iLUYMtiSEmIITUPv8lz8FGeXope0RiIWCzJbM2UTK3s3Ux9io7NebG4PFNksLkbGSiSNI83iwENbc79TmUinlVwm-ur2IjKpWuE69eLLTpVE5mQ&disp=emb&realattid=ii_kddm336521)
举例二:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.19&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ88zldwVdRPhpKM6ArqcVDxKSXESxw2-C0d-wypZtGFgL9GD5lcnt1zGIs97FzOWaoiTVPSnU_Gi1gYEortsxD8yImnl19_II30_Li5roVhIk468tO3-l7NLeA&disp=emb&realattid=ii_kddm4fhz22)
输出结果:
.split()
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.21&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9MXwm3oeQ-y-QVbU2sx8RgP19LYWRw3hbt31oUdgtNtVVp_lWgRr2-Tvdtht7iSvJzCzXpRkLp5IHvXD1CEM7yv2MgcRmPr3RkWOwMgcVg2nAY0dIdiinxHgM&disp=emb&realattid=ii_kddmkxj624)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.22&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9nnkX5LnkkjJ5byiBn0u2W__aLHMjNIz7PGi87CmkUJL8cWP0TFQb4o1Zw7ncjMPeAJZTWcrvVeTNtuWf_2hqix9J2Am3XzmsnaypYpa0ZSqH9-bcsZIT1Rf0&disp=emb&realattid=ii_kddmlp1h25)
在s3中,字符串的第一个位置是冒号:,在经过split 转换之后,变成list 中的在位置一 的空字符串。
.join() :字符串中必须只能是字符,不能是数字,否则报错。
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.23&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ8kcz6L0zvWx7F-Q_QJ0nZ9X_LGO1ss8vNM74im1Wo5R0HGZoW1JGvGd0KkxGXy5fsi3O3eAJK9qI9_TbqRT5oaVDyda33qqnl-5ODGDdWRvUq0qqYc3c1adEM&disp=emb&realattid=ii_kddmta1526)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.24&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ85rvJCgTuwhwlVG68ifZStuy63FlxlzsSJ_KHtwh9Lz1uk_xDTlYesl2bwQUUqI8WwINMNZvSFIG7hYXqSW7PybFc-AGC4Kc10tcdH7IzZ7rw7TuNk4Ux9T6g&disp=emb&realattid=ii_kddmumxw28)
.count()
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.27&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ8A-1rYA4vOoddUt0gxn22nDvLejWmHsV6XWsHvxjDUR1_XmoJWj25rdrInN4LWaZOS0HDCcLEH0Os7ftKbL1wjzr4rXPIcYMeTYF9sUEsmBBJCS7hXwxAtzu8&disp=emb&realattid=ii_kddns4fq31)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.28&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ_YwMRWatTi1Qb8TVzYCVtS3i0t2MEeZVRbh6NKeJwfgr1_18_1zLRYTDFzvRq8ZmXkMl6v4vfrTu4jtP6ZnDvMfrwB52w3u3Qykb74OBaIsh_ON-pH05R9QOY&disp=emb&realattid=ii_kddnsp7j32)
.format()
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.25&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9vMZmGqq-yNSUPYvAB27r7lvreJzqhoNULmw0wFXAjUehzrRNkd_H5rht63OXwM-JEn0tK0Nfe0JdpKsTpAfhrxYZkMQaZe6_T_OwrOolsMBjP9UVmDZOu0Hw&disp=emb&realattid=ii_kddnqcbw29)
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.26&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9a2PtJ-AYRV9hpthC5lo301i9tqJc0SRYa0ZDKuKSQM-S_Uanns97RIfTavEuix9P1c8DB6sbVpCmRgweTt-UF5_mJe29nIvO0QeY76jUWzh-LJ_TCdpQQXns&disp=emb&realattid=ii_kddnqw9730)
.isdecimal(): 用于判断输入的数字是否只是十进制的数。 可用于检查用户必须而且只能是十进制数字的情况,比如说金额。
输出结果:
举例二:
输出结果:
.split()
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.21&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9MXwm3oeQ-y-QVbU2sx8RgP19LYWRw3hbt31oUdgtNtVVp_lWgRr2-Tvdtht7iSvJzCzXpRkLp5IHvXD1CEM7yv2MgcRmPr3RkWOwMgcVg2nAY0dIdiinxHgM&disp=emb&realattid=ii_kddmkxj624)
输出结果:
在s3中,字符串的第一个位置是冒号:,在经过split 转换之后,变成list 中的在位置一 的空字符串。
.join() :字符串中必须只能是字符,不能是数字,否则报错。
举例:
输出结果:
.count()
举例:
输出结果:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.28&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ_YwMRWatTi1Qb8TVzYCVtS3i0t2MEeZVRbh6NKeJwfgr1_18_1zLRYTDFzvRq8ZmXkMl6v4vfrTu4jtP6ZnDvMfrwB52w3u3Qykb74OBaIsh_ON-pH05R9QOY&disp=emb&realattid=ii_kddnsp7j32)
.format()
举例:
![image.png](https://mail.google.com/mail/u/1?ui=2&ik=aa05b841ff&attid=0.25&permmsgid=msg-a:r-444525330532721222&th=173b1596e49b0bfa&view=fimg&sz=s0-l75-ft&attbid=ANGjdJ9vMZmGqq-yNSUPYvAB27r7lvreJzqhoNULmw0wFXAjUehzrRNkd_H5rht63OXwM-JEn0tK0Nfe0JdpKsTpAfhrxYZkMQaZe6_T_OwrOolsMBjP9UVmDZOu0Hw&disp=emb&realattid=ii_kddnqcbw29)
输出结果:
.isdecimal(): 用于判断输入的数字是否只是十进制的数。 可用于检查用户必须而且只能是十进制数字的情况,比如说金额。
标签:输出,结果,Python,print,举例,人到中年,str,字符串,day
来源: https://www.cnblogs.com/shantao2020/p/13424261.html