python 异常处理
异常处理
import os # 这是用函数的形式去设定异常 def fun(path,perv): "去path路径的文件 找到前缀为perv的一行数据获取数据并返回给调用者" response={"code":100,"data":None} try: if not os.path.exists(path): response["code"]=200 # "文件不存在" 对于的代号 response["data"]="文件不存在" return response if not perv: response["code"]=300 # 文件不能空 对于的代号 response["data"]="文件不能空" return response pass except Exception as e: response["code"] = 666666 # "未知错误" 对于的代号 response["data"] = "未知错误" return response
# 用类的形式去定义抛出异常 # 自定义 异常类 1 class MyException(Exception):# 去继承Exception类 def __init__(self,code,msg): self.code=code self.msg=msg try: raise MyException(1000,"操作正常") except MyException as obj: print(obj.code,obj.msg)
自定义 异常类 2 class MyException(Exception):# 去继承Exception类 def __init__(self,code,msg): self.code=code self.msg=msg try: raise MyException(1000,"操作正常") except MyException as e: print(e.code,e.msg)
# 自定义 异常类 3 class MyException(Exception):# 去继承Exception类 def __init__(self,code,msg): self.code=code self.msg=msg try: raise MyException(1000,"操作正常") except KeyError as obj: print(obj,111111) except MyException as obj: print(obj,22222) except Exception as obj: print(obj,33333)
# 主动触发异常 try: raise Exception('错误了。。。') except Exception as e: print(e)