day7-format字符串格式化

tpl = "i am {name}, age {age}, really {name}".format(name="seven", age=18)
print(tpl)  # i am seven, age 18, really seven 必须一一对应，否则会报错


tpl = "i am {name}, age {age}, really {name}".format(**{"name": "seven", "age": 18})
# 要传字典，必须加两个**，否则会报错，作用同上
print(tpl)  #  i am seven, age 18, really seven，


tpl = "i am {2}, age {1}, really {0}".format("seven", 18,'alex')
print(tpl)  # i am alex, age 18, really seven


tpl = "i am {:s}, age {:d}".format(*["seven", 18])
# *表示传入的是列表，：s指传入的是字符串，:d指传入的是数字
print(tpl)  # i am seven, age 18


tpl = "i am {:s}, age {:d}".format("seven", 18) #["seven", 18]
print(tpl)  # i am seven, age 18
l=["seven", 18]
tpl = "i am {:s}, age {:d}".format('seven',18)
print(tpl)  # i am seven, age 18

tpl = "numbers: {:b},{:o},{:d},{:x},{:X}, {:%},{}".format(15, 15, 15, 15, 15, 15.87623, 2)
# :b指二进制 ，:o指8进制，:x\X 指16进制 :%指显示成百分比
print(tpl)  # numbers: 1111,17,15,f,F, 1587.623000%,2