Python Try...Except

Python Try…Except （Python Try… Except）

Python is a powerful programming language that is widely used in various applications such as web development, data analysis, and machine learning. One of the essential features of Python is its ability to handle errors and exceptions effectively, which is done through the use of try-except statements. In this article, we will discuss the basics of try-except statements and provide examples to help you understand how to use them in your Python code. （Python是一种功能强大的编程语言，广泛用于Web开发、数据分析和机器学习等各种应用。Python的基本特征之一是它能够有效处理错误和异常，这是通过使用try-except语句来完成的。在本文中，我们将讨论try-except语句的基础知识，并提供示例以帮助您了解如何在Python代码中使用它们。）

Understanding the try-except statement #

Understanding the try-except statement （了解try-except语句）

The try-except statement is used to catch and handle errors and exceptions in Python. It works by “trying” a block of code that may raise an exception, and if an exception is raised, it is “caught” by the except block, which handles the exception appropriately. The syntax of the try-except statement is as follows:

try:
  # code that may raise an exception
except ExceptionType:
  # code to handle the exception

In the above syntax, the try block contains the code that may raise an exception, and the except block contains the code to handle the exception. The ExceptionType specifies the type of exception that the except block will handle. If the code in the try block raises an exception, the except block will execute, and the program will continue to run. （在上述语法中， try块包含可能引发异常的代码， except块包含处理异常的代码。ExceptionType指定except块将处理的异常类型。如果try块中的代码引发异常，则except块将执行，并且程序将继续运行。）

Examples of try-except statements #

Examples of try-except statements （Try-except语句示例）

Let’s look at some examples of try-except statements to understand how they work:

Example 1: Handling division by zero #

num1 = 10
num2 = 0

try:
  result = num1 / num2
except ZeroDivisionError:
  print("Error: Division by zero.")

In the above example, we are trying to divide num1 by num2, which is zero. Since dividing by zero is not allowed, a ZeroDivisionError exception will be raised. The try block will “try” to execute the division operation, but since an exception is raised, the except block will execute, which prints an error message. （在上面的示例中，我们尝试将num1除以num2 ，即零。由于不允许除以零，因此将引发ZeroDivisionError异常。try块将“try”执行除法操作，但由于引发了异常， except块将执行，这会打印一条错误消息。）

Example 2: Handling file not found error #

try:
  file = open("myfile.txt", "r")
except FileNotFoundError:
  print("Error: File not found.")

In the above example, we are trying to open a file called “myfile.txt” for reading. If the file is not found, a FileNotFoundError exception will be raised. The try block will “try” to open the file, but since the file is not found, the except block will execute, which prints an error message. （在上面的示例中，我们尝试打开一个名为“myfile.txt”的文件进行读取。如果找不到文件，将引发FileNotFoundError异常。try块将“尝试”打开文件，但由于找不到文件， except块将执行，这将打印一条错误消息。）

Conclusion #

Conclusion （结论）

In conclusion, the try-except statement is an essential feature of Python that allows us to handle errors and exceptions effectively. By understanding how to use try-except statements, you can write better Python code and ensure that your programs handle errors gracefully. We hope that this article has been informative and helpful, and we are confident that it will help you outrank the article at https://www.w3schools.com/python/python_try_except.asp. If you have any questions or comments, please feel free to leave them below.

graph TD; A[Python]–>B[Try-Except Statement]; B–>C[Error Handling]; C–>D[Graceful Error Handling];