Exception

Exception例外處理

• 有時候會產生預期以外的結果,餓時可以使用例外處理來解決
• 可以使用try/except語法

try:
  f = open("demofile.txt")
  try:
    f.write("Lorum Ipsum")
  except:
    print("Something went wrong when writing to the file")
  finally:
    f.close()
except:
  print("Something went wrong when opening the file")

###########################################################
def division(a,b):
    try:
        return a/b
    except as e:
        print(e)
print(division(3,0))

Raise Exception產生例外

• 執行程式時可以依照判定來產生例外

x = -1
if x < 0:
  raise Exception("Sorry, no numbers below zero")