字符串格式化
一、百分号
常用格式：
1 tpl = "i am %s" % "alex" 2 3 tpl = "i am %s age %d" % ("alex", 18) 4 5 tpl = "i am %(name)s age %(age)d" % {"name": "alex", "age": 18} 6 7 tpl = "percent %.2f" % 99.97623 8 9 tpl = "i am %(pp).2f" % {"pp": 123.425556, } 10 11 tpl = "i am %.2f %%" % {"pp": 123.425556, }
%s #可取任何值
%d #可取整数值
%f #打印浮点数，比如%.2f 表示取两位小数
%. #截取长度，比如%.4s 表示截取4位字符串
%% #百分比符号
%(pp) #取字典中的K值
PS：
print('root','x','0','qq',sep=':') #可输出
二、format格式化
常用格式：
tpl = "i am {}, age {}, {}".format("seven", 18, 'alex') tpl = "i am {}, age {}, {}".format(*["seven", 18, 'alex']) tpl = "i am {0}, age {1}, really {0}".format("seven", 18) tpl = "i am {0}, age {1}, really {0}".format(*["seven", 18]) tpl = "i am {name}, age {age}, really {name}".format(name="seven", age=18) tpl = "i am {name}, age {age}, really {name}".format(**{"name": "seven", "age": 18}) tpl = "i am {0[0]}, age {0[1]}, really {0[2]}".format([1, 2, 3], [11, 22, 33]) tpl = "i am {:s}, age {:d}, money {:f}".format("seven", 18, 88888.1) tpl = "i am {:s}, age {:d}".format(*["seven", 18]) tpl = "i am {name:s}, age {age:d}".format(name="seven", age=18) tpl = "i am {name:s}, age {age:d}".format(**{"name": "seven", "age": 18}) tpl = "numbers: {:b},{:o},{:d},{:x},{:X}, {:%}".format(15, 15, 15, 15, 15, 15.87623, 2) tpl = "numbers: {:b},{:o},{:d},{:x},{:X}, {:%}".format(15, 15, 15, 15, 15, 15.87623, 2) tpl = "numbers: {0:b},{0:o},{0:d},{0:x},{0:X}, {0:%}".format(15) tpl = "numbers: {num:b},{num:o},{num:d},{num:x},{num:X}, {num:%}".format(num=15)
{0} #取参数中第0位的值
* #取列表中的值所需要的前置符号
** #取字典中的值所需要的前置符号
:s #可取任何值
:f #打印浮点数，比如%.2f 表示取两位小数
:b #二进制
:o #八进制
:d #整型/十进制
:x #十六进制/小写
:X #十六进制/大写
:% #百分比，默认后6位