面试题：Python中装饰器如何实现带参数的功能

Question

请编写一个带参数的装饰器，该装饰器用于在函数执行前后打印日志，日志内容包含传入装饰器的参数，例如传入参数 'operation'，则在函数执行前打印 'Starting operation'，执行后打印 'Finished operation'。

Answer 1

def log_decorator(operation):
    def decorator(func):
        def wrapper(*args, **kwargs):
            print(f'Starting {operation}')
            result = func(*args, **kwargs)
            print(f'Finished {operation}')
            return result
        return wrapper
    return decorator


@log_decorator('operation')
def example_function():
    print('Function is running...')


example_function()