Question

我正在开发一个程序，它将从如下文件中提取文本：

NAME OF PROGRAM: text.txt

CONTENTS OF FILE:

  1: 101010100101010101 1010010101010101 101010101010101
  2: 0101010101 1010011010 10101010 10101010 10101010
  3: 0001000101010 10101010 10101010 1010101010 10101

START LINE: 1
END LINE: 2

results.txt generated.

我在程序要求提供程序名称的部分，我计划在程序名称长度为零时使用异常。

该程序应该像：

NAME OF PROGRAM: 

THE NAME OF THE PROGRAM SHOULD NOT BE LESS THAN 1! [LEN_ERROR]

但程序运行如此：

NAME OF PROGRAM:
THERE'S SOMETHING WRONG WITH YOUR INPUT! [INP_ERROR]

以下是代码：

class Program:
    """
      Author       : Alexander B. Falgui (alexbfalgui.github.io)
      Program Name : Text Extractor
      Description  : Takes an integer or string as an input and generates a
      text file with the extracted data. 

      Note: This program can be used, shared, modified by anyone.
    """

    def __init__(self):
        self.menu_file_loc = "menu"
        return self.load_files()

    def load_files(self):
        #self.menu_file = open(self.menu_file_loc)
        #self.read_mf = self.menu_file.read()

        return self.main_menu()

    def main_menu(self):
        #print(self.read_mf)
        print("""  [1] Extract Data\n  [2] Exit""")

        while (True):
            try:
              self.menu_input = input("CHOOSE AN OPTION> ")
              if (self.menu_input == 1):
                  try:
                    self.program_name = raw_input("\nNAME OF THE PROGRAM: ")
                    self.program_name = open(self.program_name)
                  except IOError:
                    if (len(program_name) == 0):
                      print("THE NAME OF THE PROGRAM SHOULD NOT BE LESS THAN"),
                      print(" 1! [LEN_ERROR]")

                    print("%s does not exist" % self.program_name)
              elif (self.menu_input == 0):
                  print("\n")
                  break

            except SyntaxError:
                continue
            except NameError:
                print("SOMETHING'S WRONG WITH YOUR INPUT. [INP_ERROR]\n")

# Run the program
Program()

为什么程序会打印错误的异常，我该怎么做才能解决这个问题？

Answer 1

请不要except SyntaxError: continue，因为您会默默地检查任何语法错误。

要获得有关出错的更多信息，您应except NameError as e进一步调查。另请参阅https://docs.python.org/2/tutorial/errors.html

您应该将except NameError - 部分更改为以下内容：

        except NameError as e:
            print e
            print("SOMETHING'S WRONG WITH YOUR INPUT. [INP_ERROR]\n")

你会看到出了什么问题。

Answer 2

我不确定为什么你在最后添加了这两个异常处理程序，但是你得到了一个名称异常，因为你引用了 program_name 变量而不是 self.program_name

将您的专线if (len(program_name) == 0):更改为if (len(self.program_name) == 0):，它应该有效。

程序不打印预期的异常

2 个答案: