字符串格式化

Posted 2021-02-12 romacle

　　python中使用format格式化字符串

　　通过位置格式化

info = ‘my name is {0} and i am {1} old , job is {0} ‘
print(info.format(‘xxx‘,18))
>>>my name is xxx and i am 18 old , job is xxx 

　　如果format后的元组内的元素个数少于要格式化字符的个数，则必须在要格式化的字符处添加元组元素的索引位置。否则会抛出异常。

info = ‘my name is {} and i am {} old , job is {} ‘  #格式化3个字符
print(info.format(‘xxx‘,18))                         #只有两个元素
>>>IndexError: tuple index out of range              #报错

　　如果要格式化的字符个数少于元组元素的数量，则会顺序添加

info = ‘my name is {} and i am {} old ‘   #格式化2个字符
print(info.format(‘xxx‘,18,‘454‘,‘abc‘))  # 元组内包含4个元素
>>>my name is xxx and i am 18 old         #顺序添加 ，多余的忽略

　　

　　通过key来格式化

info = ‘my name is {name} and i am {age} old , job is {work} ‘
print(info.format(name=‘xxx‘,age=18,work=‘IT‘))
>>>my name is xxx and i am 18 old , job is IT 

 

　　通过下标格式化

data = [‘xxx‘,18,‘IT‘]
info = ‘my name is {data[0]} and i am {data[1]} old , job is {data[2]} ‘
print(info.format(data=data))
>>>my name is xxx and i am 18 old , job is IT 


info = ‘my name is {0[0]} and i am {0[1]} old , job is {0[2]} ‘
print(info.format(data))
>>>my name is xxx and i am 18 old , job is IT 

　　

　　通过字典的key

data = {‘name‘:‘xxx‘,‘age‘:18,‘job‘:‘IT‘}
info = ‘my name is {aaa[name]} and i am {aaa[age]} old , job is {aaa[job]} ‘
print(info.format(aaa=data))
>>>my name is xxx and i am 18 old , job is IT 

　　

　　#其他方法暂略。。。