Python字符串格式化实例讲解

name = "Eric"
age = 74
"Hello, %s. You are %s." % (name, age)

"Hello, {}. You are {}.".format(name, age)

"Hello, {1}. You are {0}-{0}.".format(age, name)

person = {'name': 'Eric', 'age': 74}
"Hello, {name}. You are {age}.".format(name=person['name'], age=person['age'])

person = {'name': 'Eric', 'age': 74}
"Hello, {name}. You are {age}.".format(**person)

name = "Eric"
age = 74
f"Hello, {name}. You are {age}."

name = "Eric"
age = 74
F"Hello, {name}. You are {age}."

name = "Eric"
age = 74
f"{name.lower()} is funny."

f"{2 * 37}"

class Comedian:
    def __init__(self, first_name, last_name, age):
        self.first_name = first_name
        self.last_name = last_name
        self.age = age
    def __str__(self):
        return f"{self.first_name} {self.last_name} is {self.age}."
    def __repr__(self):
        return f"{self.first_name} {self.last_name} is {self.age}. Surprise!"
new_comedian = Comedian("Eric", "Idle", "74")
f"{new_comedian}"

f"{new_comedian!r}"

message = (f"Hi {name}. "
        f"You are a {profession}. "
        f"You were in {affiliation}.")

message = (f"Hi {name}. "
        "You are a {profession}. "
        "You were in {affiliation}.")

message = f"""
    Hi {name}. 
    You are a {profession}. 
    You were in {affiliation}.
 """

'''
学习中遇到问题没人解答？小编创建了一个Python学习交流群：711312441
寻找有志同道合的小伙伴，互帮互助,群里还有不错的视频学习教程和PDF电子书！
'''
%%timeit
name = "Eric" 
age = 74 
'%s is %s.' % (name, age)
# 202 ns ± 2.05 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)
%%timeit
name = "Eric" 
age = 74 
'{} is {}.'.format(name, age)
# 244 ns ± 5.52 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)
%%timeit
name = "Eric" 
age = 74 
'{name} is {age}.'
# 14.4 ns ± 0.0121 ns per loop (mean ± std. dev. of 7 runs, 100000000 loops each)

f"{'Eric Idle'}"

f'{"Eric Idle"}'

f"""Eric Idle"""

f'''Eric Idle'''

f"The \"comedian<span class="string">" is {name}, aged {age}."

comedian = {'name': 'Eric Idle', 'age': 74}
f"The comedian is {comedian['name']}, aged {comedian['age']}."

f"{{74}}"

f"{{{{74}}}}"