Python基础——异常

捕捉所有异常

for i in range(10):
    try:
        input_number=input('write a number')
        if input_number=='q':
            break
        result=math.log(float(input_number))
        print(result)
    except Exception:
        print('ValueError:input must > 0')
        break

捕捉指定异常

for i in range(10):
    try:
        input_number=input('write a number')
        if input_number=='q':
            break
        result=1/math.log(float(input_number))
        print(result)
    except ValueError:
        print('ValueError:input must > 0')
    except ZeroDivisionError:
        print('不能除0')

自定义异常

class TestError(ValueError):
    pass

cur_list=['hello','world']
while True:
    cur_input=input()
    if cur_input not in cur_list:
        raise TestError('Invalid input')

finally

无论是否异常，都会执行finally中的代码。

try:
    1/0
except:
    print('==0')
finally:
    print('finally')