Python - 我的类引发了ValueError,但它不是由except处理的

时间:2015-02-10 17:57:19

标签: python exception raise

我的示例代码:

from tkinter import *

class first:
    def __init__(self):
        self.top = Tk()
        ...
    def test(self):
        try:
            self.value = self.dict[key]
        except KeyError:
            try:
                second()
            except ValueError:
                print('Finally')

class second:
    def __init__(self):
        self.frame = Toplevel()
        ...
        self.button = ttk.Button(parent=self.frame, text='GO', command=self.go_click)
        ...

    def go_click(self):
        raise ValueError('Not Valid')

这只是一个例子!问题是ValueError是由第二个类引发的,但它不是由第一个类的except子句处理的。回溯下方:

Exception in Tkinter callback
Traceback (most recent call last):
File "C:\Python34\lib\tkinter\__init__.py", line 1487, in __call__
    return self.func(*args)
File "........", line xxx, in goclick
    raise ValueError('Not Valid')
ValueError: Not Valid

我该如何妥善处理?

谢谢,

1 个答案:

答案 0 :(得分:-1)

试试这个

from tkinter import *

class first:
    def __init__(self):
        self.top = Tk()
        ...
    def test(self):
        try:
            self.value = self.dict[key]
        except KeyError:
            try:
                second()
            except ValueError:
                print('Finally')
            print "OK CALLED SECOND()!!!!" #######THIS PRINT MEANS YOUR DONE HERE

class second:
    def __init__(self):
        self.frame = Toplevel()
        ...
        self.button = ttk.Button(parent=self.frame, text='GO', command=self.go_click)
        ...

    def go_click(self):
        raise ValueError('Not Valid')

为了实际处理该错误,您需要覆盖tkinters事件循环...不是很容易(或一般的好习惯)

更好的方法是处理go_click函数中的错误本身就像

  def go_click(self):
      try:
         self.submit_form()
      except ValueError:
         print "VALIDATION ERROR!!"