.NET Exception Handling Best Practices
Discover best practices for handling exceptions in .NET applications, including global exception handling, logging, and custom exception design.
Introduction to Exception Handling
Exception handling is a crucial aspect of developing reliable and maintainable .NET applications. It allows developers to gracefully handle errors and ensure the application remains robust even under unexpected circumstances.
Why Exception Handling Matters
- Improved User Experience: Proper exception handling ensures users are not exposed to confusing error messages.
- Application Stability: Catching and managing exceptions prevents application crashes.
- Debugging and Monitoring: Logging exceptions aids in identifying and fixing issues.
Basic try-catch Usage
The try-catch block is the foundation of exception handling in .NET:
try
{
// Code that may throw an exception
int result = 10 / 0;
}
catch (DivideByZeroException ex)
{
Console.WriteLine($"Error: {ex.Message}");
}
Creating Custom Exceptions
Custom exceptions provide a way to define meaningful error types:
public class InvalidUserInputException : Exception
{
public InvalidUserInputException(string message) : base(message) { }
}
Usage example:
throw new InvalidUserInputException("The user input is invalid.");
Global Exception Handling in ASP.NET Core
Use middleware to handle exceptions globally in ASP.NET Core:
app.UseExceptionHandler(errorApp =>
{
errorApp.Run(async context =>
{
context.Response.ContentType = "application/json";
context.Response.StatusCode = 500;
await context.Response.WriteAsync("An unexpected error occurred.");
});
});
Exception Logging Best Practices
Log exceptions using a logging framework like Serilog or NLog:
catch (Exception ex)
{
logger.LogError(ex, "An error occurred while processing the request.");
}
Best Practices for Exception Handling
- Avoid swallowing exceptions without logging.
- Use specific exceptions instead of general
Exception. - Leverage global exception handling for centralized management.
- Include contextual information in exception logs.
Common Mistakes to Avoid
- Using exceptions for control flow.
- Not logging exceptions.
- Ignoring exceptions silently.
Conclusion
Exception handling is essential for building robust and maintainable .NET applications. By following best practices and leveraging tools like logging frameworks and global exception handling, you can ensure your application is reliable and user-friendly.