Error Handling Mechanism In C#
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C# Error Handling Framework
Exception Handling Exceptions and Exception Handling Exception Handling Exception Handling Exception Handling Using Exceptions Exception Handling Creating and Throwing Exceptions Compiler-Generated Exceptions How to: Handle an Exception Using try/catch How
C# Error Handling Techniques
to: Execute Cleanup Code Using finally How to: Catch a non-CLS Exception TOC Collapse the table of content Expand the table of content This documentation is archived and is not being maintained. This documentation is archived and is not being maintained. Exception Handling (C# Programming Guide) Visual Studio 2015 Other Versions Visual Studio 2013 Visual Studio 2012 Visual Studio c# error handling class 2010 Visual Studio 2008 Visual Studio 2005 A try block is used by C# programmers to partition code that might be affected by an exception. Associated catch blocks are used to handle any resulting exceptions. A finally block contains code that is run regardless of whether or not an exception is thrown in the try block, such as releasing resources that are allocated in the try block. A try block requires one or more associated catch blocks, or a finally block, or both.The following examples show a try-catch statement, a try-finally statement, and a try-catch-finally statement. C# Copy try { // Code to try goes here. } catch (SomeSpecificException ex) { // Code to handle the exception goes here. // Only catch exceptions that you know how to handle. // Never catch base class System.Exception without // rethrowing it at the end of the catch block. } C# Copy try { // Code to try goes here. } finally { // Code to execute after the try block goes here. } C# Copy try { // Cod
resources Windows Server 2012 resources Programs MSDN subscriptions Overview Benefits Administrators Students Microsoft Imagine Microsoft Student Partners ISV Startups TechRewards Events Community Magazine Forums error handling in c# best practices Blogs Channel 9 Documentation APIs and reference Dev centers Retired content error handling c# mvc Samples We’re sorry. The content you requested has been removed. You’ll be auto redirected in 1 c# exception handling best practices second. Development Guide Application Essentials Exceptions Exceptions Best Practices for Exceptions Best Practices for Exceptions Best Practices for Exceptions Exception Class and Properties Exception Hierarchy Exception Handling https://msdn.microsoft.com/en-us/library/ms173162.aspx Fundamentals Best Practices for Exceptions Handling COM Interop Exceptions TOC Collapse the table of content Expand the table of content This documentation is archived and is not being maintained. This documentation is archived and is not being maintained. Best Practices for Exceptions .NET Framework (current version) Other Versions Visual Studio 2010 .NET Framework 4 Silverlight https://msdn.microsoft.com/en-us/library/seyhszts(v=vs.110).aspx .NET Framework 3.5 .NET Framework 3.0 .NET Framework 2.0 .NET Framework 1.1 A well-designed app handles exceptions and errors to prevent app crashes. This article describes best practices for handling and creating exceptions.Handling exceptionsThe following list contains some general guidelines for handling exceptions in your app.Use exception handling code (try/catch blocks) appropriately. You can also programmatically check for a condition that is likely to occur without using exception handling. Programmatic checks. The following example uses an if statement to check whether a connection is closed. If it isn't, the example closes the connection instead of throwing an exception. C#C++VB Copy if (conn.State != ConnectionState.Closed) { conn.Close(); } Exception handling. The following example uses a try/catch block to check the connection and to throw an exception if the connection is not closed. C#C++VB Copy try { conn.Close(); } catch (InvalidOperationException ex) { Console.WriteLine(ex.GetType().FullName); Console.WriteLine(ex.Message); } The method you choose depends on how often you expect the event to occur. Use exception handling if
Disconnected Data – The DataSet and SqlDataAdapter Lesson 06: Adding Parameters to Commands Lesson 07: Using Stored Procedures C# Tutorial http://csharp-station.com/Tutorial/CSharp/Lesson15 Lesson 1: Getting Started with C# Lesson 2: Operators, Types, and Variables Lesson 3: Control Statements – Selection Lesson 4: Control Statements – Loops Lesson 5: Methods Lesson http://csharp.net-tutorials.com/advanced/exceptions/ 6: Namespaces Lesson 7: Introduction to Classes Lesson 8: Class Inheritance Lesson 9: Polymorphism Lesson 10: Properties Lesson 11: Indexers Lesson 12: Structs Lesson 13: Interfaces Lesson 14: error handling Introduction to Delegates and Events Lesson 15: Introduction to Exception Handling Lesson 16: Using Attributes Lesson 17: Enums Lesson 18: Overloading Operators Lesson 19: Encapsulation Lesson 20: Introduction to Generic Collections Lesson 21: Anonymous Methods Lesson 22: Topics on C# Type Lesson 23: Working with Nullable Types LINQ Tutorial Lesson 01: Introduction to LINQ Lesson c# error handling 02: Forming Projections Articles Links ASP.NET Sites C# Sites .NET Sites Job Sites Object Oriented Sites Other Sites Tools VB.NET Sites Web Services Sites About Contact Link to C# Station Submit a site Support C# Station Terms of Service Lesson 15: Introduction to Exception Handling This lesson teaches how to handle exceptions in your C# programs. Our objectives are as follows: Learn what an exception is Implement a routine with a try/catch block Release resources in a finally block Exceptions Exceptions are unforeseen errors that happen in your programs. Most of the time, you can, and should, detect and handle program errors in your code. For example, validating user input, checking for null objects, and verifying the values returned from methods are what you expect, are all examples of good standard error handling that you should be doing all the time. However, there are times when you don't know if an error will occur. For example, you can't predict when you'll receive a file I/
help us prevent some of the most common mistakes. Obviously it can't see every error that might happen, and in those cases, the .NET framework will throw an exception, to tell us that something went wrong. In an earlier chapter, about arrays, I described how we would get an exception if we tried to stuff too many items into an array. Let's bring the example: using System; using System.Collections; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { int[] numbers = new int[2]; numbers[0] = 23; numbers[1] = 32; numbers[2] = 42; foreach(int i in numbers) Console.WriteLine(i); Console.ReadLine(); } } } Okay, try running this example, and you will see what I'm talking about. Do you see what we're doing wrong? We have defined an array of integers with room for 2 items, yet we try to use 3 spaces in it. Obviously, this leads to an error, which you will see if you try to run this example. When run inside Visual C# Express, the IDE gives us some options for the exception, but if you try to execute the program by simply doubleclicking the EXE file, you will get a nasty error. If you know that an error might occur, you should handle it. This is where exceptions are used. Here is a slightly modified version of the code from above: int[] numbers = new int[2]; try { numbers[0] = 23; numbers[1] = 32; numbers[2] = 42; foreach(int i in numbers) Console.WriteLine(i); } catch { Console.WriteLine("Something went wrong!"); } Console.ReadLine(); Let me introduce to you your new best friend when it comes to error handling: the try..catch block. Try running the program now, and see the difference - instead of Visual C# Express/Windows telling us that a serious problem occured, we get to tell our own story. But wouldn't it be nice if we could tell what went