format字符串格式化

1.format()格式方法传值时，必须要一一对应，如果不对应则会报错

# format()格式方法传值时，必须要一一对应，如果不对应则会报错
tpl = "i am {},age {},{}".format("seven",18,'alex')
print(tpl)

#可以通过索引来传值
tpl = "i am {0},age {1},{2}".format("seven",18,'alex')
print(tpl)
#索引位置不同，则传过来的值不同
tpl = "i am {2},age {1},{0}".format("seven",18,'alex')
print(tpl)

2.其他传值方式

# 可通过字典的方式传值
tpl = "i am {name},age {age},really {name}".format(name ='seven',age =18)
print(tpl)
tpl = "i am {name},age {age},really {name}".format(**{"name" :'seven',"age" :18})
print(tpl)

#可通过列表的方式传值
tpl = "i am {0[0]},age {0[1]},really {0[2]}".format([1,2,3],[11,22,33])
print(tpl)
# 字典与类型取值联合使用
tpl = "i am {name:s},age {age:d}".format(name="seven",age =18)
print(tpl)
tpl = "i am {:s},age {:d}".format("seven",18)
print(tpl)