python格式化字符串4种方法_python 表达式指令 格式化字符串

1.格式化字符串写法

废话不多说，直接上代码

def str_format():
    context1 = '''there is a person, name: %s, age: %d, salary: %d''' %("lucy", 18, 2000)
    context2 = '''there is a person, name: %(name)s, age: %(age)d, salary: %(salary)d''' %dict(name="lili",age=19, salary=3000)
    context3 = '''there is a person, name: {0}, age: {1}, salary: {2}'''.format("koko", 20, 4000)
    # 3.6以后的版本，推荐使用
    name, age, salary = "hanmeimei", 16, 6000
    context4 = f'''there is a person, name is {name}, age is: {age}, salary is: {salary}'''

    print(context1)
    print(context2)
    print(context3)
    print(context4)
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代码输出

there is a person, name: lucy, age: 18, salary: 2000
there is a person, name: lili, age: 19, salary: 3000
there is a person, name: koko, age: 20, salary: 4000
there is a person, name is hanmeimei, age is: 16, salary is: 6000
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f-string， formatted string literals，是python 3.6以后引入的操作。在此之前，格式化字符串常用的方法为%格式化与str.format()的方法。

而采用f-string方法，好处主要如下：
1.操作更加直观：{}标明直接被替换的变量。
2.操作更加简单：直接在字符串前面加上f即可。
3.性能也要更优于传统的格式化方法。