try...expect...finally结构

try...expect...finally结构中，finally块无论是否发生异常都会被执行，通常用来释放try块中申请的资源

 1 try:
 2     a = int(input('请输入一个被除数'))
 3     b = int(input('请输入除数'))
 4     c = float(a)/float(b)
 5 
 6 except ZeroDivisionError:
 7     print('异常，被除数不能为零')
 8 except ValueError:
 9     print('异常，不能输入字符串！')
10 except NameError:
11     print('异常，变量不存在！')
12 
13 except BaseException as e:
14     print(e)
15 
16 else:
17     print(c)
18 finally:
19     print('给我继续执行！！')
20 print('程序结束')

 

 

 1 try:
 2     f = open('d:/dddd.text','r')
 3     content = f.readline()
 4     print(content)
 5 
 6 except:
 7     print('文件未找到')
 8 
 9 finally:
10     print('关闭资源')
11     try:
12         f.close()
13     except BaseException as e:
14         print(e)
15 
16 print('程序运行结束')