exception UnicodeWarning¶ Base class for warnings related to Unicode. In the first one, we use the message attribute of the exception object. 8.3. 3. Handling Exceptions¶. Note: A user generated interrupt will raise a Keyboard Interrupt exception. Example try: a = 7/0 print float(a) except BaseException as e: print e.message Output integer division or modulo by zero It is feasible to program selected exceptions through programming. Exception Handling. exception FutureWarning¶ Base class for warnings about deprecated features when those warnings are intended for end users of applications that are written in Python. Python3 错误和异常 作为 Python 初学者，在刚学习 Python 编程时，经常会看到一些报错信息，在前面我们没有提及，这章节我们会专门介绍。 Python 有两种错误很容易辨认：语法错误和异常。 Python assert（断言）用于判断一个表达式，在表达式条件为 false 的时候触发异常。 13 comments Comments. Copy link Quote reply Contributor aaugustin commented Oct 31, 2016. Look at the following example, which asks the user for input until a valid integer has been entered, but allows the user to interrupt the program (using Control-C or whatever the operating system supports); note that a user-generated interruption is signalled by raising the KeyboardInterrupt exception. Python exception messages can be captured and printed in different ways as shown in two code examples below. Python 3 This is a tutorial in Python3, but this chapter of our course is available in a version for Python 2.x as well: Exception Handling in Python 2.x. The current implementation (perhaps since version 2?) Look at the following example: It will always require user input until enter a valid integer, but allows the user to interrupt the program (using Control-C or any method supported by the system).. Training Classes This website aims at providing you with educational material suitable for self-learning. exception ImportWarning¶ Base class for warnings about probable mistakes in module imports. It is possible to write programs that handle selected exceptions.

raise exception – No argument print system default message; raise exception (args)– with an argument to be printed; raise – without any arguments re-raises the last exception; raise exception (args) from original_exception – contain the details of the original exception In Python 3 there are 4 different syntaxes of raising exceptions.