Python，如何在捕获异常后使程序继续运行

Question

probably a simple question as I fairly new to python and programming in general but I am currently working on improving a program of mine and can't figure out how to keep the program going if an exception is caught. Maybe I am looking at it the wrong way but for example I have something along these lines:

    self.thread = threading.Thread(target=self.run)
    self.thread.setDaemon(True)
    self.thread.start()

    def run(self):
        logging.info("Starting Awesome Program") 
        try:
            while 1:
                awesome_program(self)
    except:
        logging.exception('Got exception on main handler')
        OnError(self)

    def OnError(self):
        self.Destroy()

Obviously I am currently just killing the program when an error is reached. awesome_program is basically using pyodbc to connect and run queries on a remote database. The problem arises when connection is lost. If I don't catch the exceptions the program just freezes so I set it up as it is above which kills the program but this is not always ideal if no one is around to manually restart it. Is there an easy way to either keep the program running or restert it. Feel free to berate me for incorrect syntax or poor programming skills. I am trying to teach myself and am still very much a novice and there is plenty I don't understand or am probably not doing correctly. I can post more of the code if needed. I wasn't sure how much to post without being overwhelming.

Answer 1

Catch the exception within the loop, and continue, even if an exception is caught.

def run(self):
        logging.info("Starting Awesome Program") 
        while 1:
            try:
                awesome_program(self)
            except:
                logging.exception('Got exception on main handler')
                OnError(self)

BTW:

• Your indentation seems messed up.
• I'd prefer while True . Python has bool type, unlike C, so when a bool is expected - give while a bool.

Answer 2

You're looking for this:

def run(self):
     while True:
         try:
             do_things()
         except Exception as ex:
             logging.info("Caught exception {}".format(ex))

Answer 3

Take a look at Python Exception Handling , and in particular Try...Except . It will allow you to catch particular errors and handle them however you choose fit, even ignore them completely, if possible. For example:

try:
    while something == True:
        do_stuff()
except ExceptionType:
    print "Something bad happened!" #An error occurred, but the script continues
except:
    print "Something worse happened!"
    raise #a worse error occurred, now we kill it
do_more_stuff()