What does python string formatting mean?-Python Tutorial-php.cn

What does python string formatting mean?

步履不停

Release： 2019-07-29 09:27:08

Original

9005 people have browsed it

What does python string formatting mean?

Python string formatting means using the format function to format a string.

Usage: It uses {} and: to replace the traditional % method.

1. Use positional parameters

Key points: From the following example, we can see that positional parameters are not subject to order constraints and can be {}, as long as there are corresponding parameter values in the format. The parameter index starts from 0, and the incoming positional parameter list can be *list

>>> li = ['hoho',18]
>>> 'my name is {} ,age {}'.format('hoho',18)
'my name is hoho ,age 18'
>>> 'my name is {1} ,age {0}'.format(10,'hoho')
'my name is hoho ,age 10'
>>> 'my name is {1} ,age {0} {1}'.format(10,'hoho')
'my name is hoho ,age 10 hoho'
>>> 'my name is {} ,age {}'.format(*li)
'my name is hoho ,age 18'

Copy after login

2. Use keyword parameters

Key points: the keyword parameter values must match, and a dictionary can be used as a keyword parameter To pass in the value, just add ** in front of the dictionary

>>> hash = {'name':'hoho','age':18}
>>> 'my name is {name},age is {age}'.format(name='hoho',age=19)
'my name is hoho,age is 19'
>>> 'my name is {name},age is {age}'.format(**hash)
'my name is hoho,age is 18'

Copy after login

3. Filling and formatting

:[Filling character][Alignment<^>] [Width]

>>> &#39;{0:*>10}&#39;.format(10)  ##右对齐
&#39;********10&#39;
>>> &#39;{0:*<10}&#39;.format(10)  ##左对齐
&#39;10********&#39;
>>> &#39;{0:*^10}&#39;.format(10)  ##居中对齐
&#39;****10****&#39;

Copy after login

4. Precision and base

>>> &#39;{0:.2f}&#39;.format(1/3)
&#39;0.33&#39;
>>> &#39;{0:b}&#39;.format(10)    #二进制
&#39;1010&#39;
>>> &#39;{0:o}&#39;.format(10)     #八进制
&#39;12&#39;
>>> &#39;{0:x}&#39;.format(10)     #16进制
&#39;a&#39;
>>> &#39;{:,}&#39;.format(12369132698)  #千分位格式化
&#39;12,369,132,698&#39;

Copy after login

5. Using index

>>> li
[&#39;hoho&#39;, 18]
>>> &#39;name is {0[0]} age is {0[1]}&#39;.format(li)
&#39;name is hoho age is 18

Copy after login

Related tutorial recommendations: Python video tutorial

The above is the detailed content of What does python string formatting mean?. For more information, please follow other related articles on the PHP Chinese website!