在python中使用format()函数进行字符串格式化

在Python中，可以使用format()函数对字符串进行格式化，它的基本语法是将待格式化的字符串放在大括号{}中，然后调用format()函数来替换大括号中的内容。

下面是一些使用format()函数的例子：

1. 基本的字符串格式化：

name = "Alice"
age = 25
message = "My name is {} and I am {} years old.".format(name, age)
print(message)
# 输出: My name is Alice and I am 25 years old.

2. 指定变量位置：

name = "Alice"
age = 25
message = "My name is {0} and I am {1} years old.".format(name, age)
print(message)
# 输出: My name is Alice and I am 25 years old.

3. 指定变量的格式：

pi = 3.141592653589793
message = "The value of pi is approximately {:.2f}".format(pi)
print(message)
# 输出: The value of pi is approximately 3.14

4. 使用关键字参数：

name = "Alice"
age = 25
message = "My name is {name} and I am {age} years old.".format(name=name, age=age)
print(message)
# 输出: My name is Alice and I am 25 years old.

5. 使用字典进行格式化：

person = {"name": "Alice", "age": 25}
message = "My name is {name} and I am {age} years old.".format(**person)
print(message)
# 输出: My name is Alice and I am 25 years old.

6. 使用列表进行格式化：

data = ["Alice", 25]
message = "My name is {0[0]} and I am {0[1]} years old.".format(data)
print(message)
# 输出: My name is Alice and I am 25 years old.

format()函数支持更多的格式化选项，如填充字符，对齐方式等。你可以参考Python官方文档来了解更多的用法和选项：https://docs.python.org/3/library/string.html#format-specification-mini-language