Error Handling In C#
Contents |
resources Windows Server 2012 resources Programs MSDN subscriptions Overview Benefits Administrators Students Microsoft Imagine Microsoft Student Partners ISV Startups TechRewards Events Community Magazine Forums Blogs Channel 9 Documentation APIs and reference Dev centers Retired content Samples We’re sorry. The content you error handling in c# best practices requested has been removed. You’ll be auto redirected in 1 second. C# C# Programming Guide
C# Divide By Zero Exception
Exceptions and Exception Handling Exceptions and Exception Handling Exception Handling Exception Handling Exception Handling Using Exceptions Exception Handling Creating and Throwing c# error handling example Exceptions Compiler-Generated Exceptions How to: Handle an Exception Using try/catch How 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
Throw Custom Error C#
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 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 different types of exceptions in c# 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 { // Code to try goes here. } catch (SomeSpecificException ex) { // Code to handle the exception goes here. } finally { // Code to execute after the try (and possibly catch) blocks // goes here. } A try block without a catch or finally block causes a compiler error.Catch BlocksA catch block can specify the type of exception to catch. The type specification is called an exception filter. The exception type should be derived from Exception. In g
resources Windows Server 2012 resources Programs MSDN subscriptions Overview Benefits Administrators Students Microsoft Imagine Microsoft Student Partners ISV Startups TechRewards Events Community Magazine Forums Blogs Channel 9 Documentation APIs and reference Dev centers Retired content Samples We’re
C# Exception Tutorial
sorry. The content you requested has been removed. You’ll be auto redirected in
C# Raise Exception In Try
1 second. Development Guide Application Essentials Exceptions Exceptions Best Practices for Exceptions Best Practices for Exceptions Best Practices for Exceptions throw exception in catch block c# Exception Class and Properties Exception Hierarchy Exception Handling 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 https://msdn.microsoft.com/en-us/library/ms173162.aspx 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 .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 https://msdn.microsoft.com/en-us/library/seyhszts(v=vs.110).aspx 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 the event doesn't occur very often, that is, if the event is truly exceptional and indicates an error (such as an unexpected end-of-file). When you use exception handling, less code is executed in normal conditions.Use the programmatic method to check for errors if the event happens routinely and could be considered part of normal execution. When you check for errors programmatically, more code is executed if an exception occurs.Use try/catch blocks around code that can potentially generate a
- Basic Syntax C# - Data Types C# - Type Conversion C# - Variables C# - Constants C# - Operators C# - Decision Making C# - Loops C# - Encapsulation C# - Methods C# - http://www.tutorialspoint.com/csharp/csharp_exception_handling.htm Nullables C# - Arrays C# - Strings C# - Structure C# - Enums C# http://csharp-station.com/Tutorial/CSharp/Lesson15 - Classes C# - Inheritance C# - Polymorphism C# - Operator Overloading C# - Interfaces C# - Namespaces C# - Preprocessor Directives C# - Regular Expressions C# - Exception Handling C# - File I/O C# Advanced Tutorial C# - Attributes C# - Reflection C# - Properties C# - Indexers C# - Delegates C# - Events C# - error handling Collections C# - Generics C# - Anonymous Methods C# - Unsafe Codes C# - Multithreading C# Useful Resources C# - Questions and Answers C# - Quick Guide C# - Useful Resources C# - Discussion Selected Reading Developer's Best Practices Questions and Answers Effective Resume Writing HR Interview Questions Computer Glossary Who is Who C# - Exception Handling Advertisements Previous Page Next Page An exception is a problem that arises during the error handling in execution of a program. A C# exception is a response to an exceptional circumstance that arises while a program is running, such as an attempt to divide by zero. Exceptions provide a way to transfer control from one part of a program to another. C# exception handling is built upon four keywords: try, catch, finally, and throw. try: A try block identifies a block of code for which particular exceptions is activated. It is followed by one or more catch blocks. catch: A program catches an exception with an exception handler at the place in a program where you want to handle the problem. The catch keyword indicates the catching of an exception. finally: The finally block is used to execute a given set of statements, whether an exception is thrown or not thrown. For example, if you open a file, it must be closed whether an exception is raised or not. throw: A program throws an exception when a problem shows up. This is done using a throw keyword. Syntax Assuming a block raises an exception, a method catches an exception using a combination of the try and catch keywords. A try/catch block is placed around the code that might generate an exception. Code within a try/catch block is referred to as p
Disconnected Data – The DataSet and SqlDataAdapter Lesson 06: Adding Parameters to Commands Lesson 07: Using Stored Procedures C# Tutorial 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 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: 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 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/O error, run out of system memory, or encounter a database error. These things are generally unlikely, but they could still happen and you want to be able to deal with them when they do occur. This is where exception handling comes in. When exceptions occur, they are said to be "thrown". What is actually thrown is an object that is derived from the System.Exception class. In the next section, I'll be explaining how thrown exceptions are handled with try/catch blocks. The System.Except