异常中的finally

  • finally的功能和用法

功能

  • 无论是否发生异常 ， 一定会执行的代码块
  • 在函数中， 即便在try或except中进行了return也依然会执行finally语法块
  • try语法至少要伴随except或finally中的一个

用法

try:
<代码块1>
except:
<代码块2>
finally:
<代码块3>
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历史

  • 在python 2.5 之前的版本， finally需要独立使用，不可以和try配合，之后才演变成现在的模式

代码

# coding:utf-8
def test1():
try:
1 / 0
except Exception as e:
print(e)
finally:
return 'finally'
result = test1()
print(result)
def test2():
try:
1 / 0
except Exception as e:
print('111')
return e
finally:
print('finally')
print('-------')
result = test2()
print(result)
def test3():
try:
print('try test 11')
return 'try'
except Exception as e:
print('e')
finally:
print('finally test')
print('------')
result = test3()
print(result)
def test4():
try:
1 / 0
except Exception as e:
print('1')
return e
finally:
print('2')
return 'finally'
print('----------')
result = test4()
print(result)
def test5():
try:
print('1try')
return 'try'
except Exception as e:
print('e')
finally:
print('2finally')
return 'finally'
print('========')
result = test5()
print(result)
def test6():
try:
print('try1')
1 / 0
print('try3')
finally:
# print('i am finally')
return 'i am finally'
print('-------')
result = test6()
print(result)
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