Error Handling Code In Vb.net
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 requested has been removed. You’ll be auto redirected in 1 second. .NET Development Articles and Overviews Upgrading to Microsoft .NET Upgrading to Microsoft .NET Error Handling in Visual Basic .NET Error Handling in Visual Basic .NET Error Handling in Visual Basic .NET ADO.NET for the ADO Programmer Building an N-Tier Application in .NET Calling a .NET Component from a COM Component Calling COM Components from .NET Clients Common .NET Libraries for Developers Comparing System.Xml in Visual Studio .NET to Microsoft.XMLDOM in Visual Studio 6.0 Converting ASP to ASP.NET Creating Classes in Visual Basic .NET Creating Components in .NET Creating a Windows Form User Control Data Binding with Windows Forms and ADO.NET Designing a .NET Application Designing for Web or Desktop? Determining When to Use Windows Installer Versus XCOPY Differences Between Visual Basic 6.0 and .NET Controls Distributed Transactions in Visual Basic .NET Error Handling in Visual Basic .NET Getting Started with Windows Forms Inheritance and Interfaces Inheritance from a Base Class in Microsoft .NET Interacting with Message Queues Introduction to ASP.NET and Web Forms Introduction to Visual Studio .NET Managing Versions of an Application Migrating from the SOAP Toolkit to Web Services Overloading Methods in Visual Basic .NET Performing Drag-and-Drop Operations Raising Events and Responding to Events Replacing API Calls with .NET Framework Classes Structuring a .NET Application For Easy Deployment Understanding and Using Assemblies and Namespaces in .NET Using ActiveX Controls with Windows Forms in Visual Studio .NET Using ADO.NET Using COM+ Services in .NET Using Web Services Instead of DCOM Variable and Method Scope in Microsoft .NET Working with MDI Applications and Creating Menus 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. Error Handling in Visual Basic .NET Ken Getz MCW Technologies February 2002 Summary: Discusses how error handling differs between Visual Basic .NET and Visual Basic 6.0. Main topics include Try/Catch blocks, Exce
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 requested has been removed. You’ll be auto redirected in 1 second. Visual Basic Language Reference Statements Q-Z Statements Q-Z Statements Try...Catch...Finally Statement Try...Catch...Finally Statement Try...Catch...Finally Statement RaiseEvent Statement ReDim Statement REM Statement RemoveHandler Statement Resume Statement Return Statement Select...Case Statement Set Statement Stop Statement Structure Statement Sub Statement SyncLock Statement Then Statement Throw Statement Try...Catch...Finally Statement Using Statement While...End While Statement With...End With Statement Yield https://msdn.microsoft.com/en-us/library/ms973849.aspx Statement 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. Try...Catch...Finally Statement (Visual Basic) Visual Studio 2015 Other Versions Visual Studio 2013 Visual Studio 2012 Visual Studio 2010 Visual Studio 2008 Visual Studio 2005 Visual Studio .NET 2003 Provides a way to handle some or all possible errors that https://msdn.microsoft.com/en-us/library/fk6t46tz.aspx may occur in a given block of code, while still running code.Syntax Copy Try [ tryStatements ] [ Exit Try ] [ Catch [ exception [ As type ] ] [ When expression ] [ catchStatements ] [ Exit Try ] ] [ Catch ... ] [ Finally [ finallyStatements ] ] End Try PartsTermDefinitiontryStatementsOptional. Statement(s) where an error can occur. Can be a compound statement.CatchOptional. Multiple Catch blocks permitted. If an exception occurs when processing the Try block, each Catch statement is examined in textual order to determine whether it handles the exception, with exception representing the exception that has been thrown. exceptionOptional. Any variable name. The initial value of exception is the value of the thrown error. Used with Catch to specify the error caught. If omitted, the Catch statement catches any exception.typeOptional. Specifies the type of class filter. If the value of exception is of the type specified by type or of a derived type, the identifier becomes bound to the exception object.WhenOptional. A Catch statement with a When clause catches exceptions only when expression evaluates to True. A When clause is applied only after checking the type of the exception, and expression may refer to the identifier representing the exception.expressionOptional. Mus
for Beginners Try ... Catch in VB .NET This lesson is part of an ongoing tutorial. The previous part is here: http://www.homeandlearn.co.uk/NET/nets5p4.html Runtime Errors VB.NET has a inbuilt class that deals with errors. The Class is called Exception. When an exception error is found, an Exception object is created. The coding structure VB.NET uses to deal with such Exceptions is called the Try Catch structure. In the coding area for your button, type the word Try. Then hit the return key on your error handling keyboard. VB.NET completes the rest of the structure for you: Try Catch ex As Exception End Try The Try word means "Try to execute this code". The Catch word means "Catch any errors here". The ex is a variable, and the type of variable it is is an Exception object. Move your line of code from the previous section to the Try part: Try error handling code rt1.LoadFile("C:\test10.txt", RichTextBoxStreamType.PlainText) Catch ex As Exception End Try When you run your programme, VB will Try to execute any code in the Try part. If everything goes well, then it skips the Catch part. However, if an error occurs, VB.NET jumps straight to Catch. Add the following to your Catch part: MessageBox.Show(ex.Message) Your coding window should look like this: Because ex is an object variable, it now has its own Properties and methods. One of these is the Message property. Run your programme and test it out. Click your button. You should see the following error message: The message is coming from the "additional Information" section of the error message we saw earlier, the one we didn't handle. But the point about this new message box is that it will not crash your programme. You have handled the Exception, and displayed an appropriate message for the user. If you know the kind of error that a programme might throw, you can get what Type it is from the Error message box you saw earlier. This one: Click the View Details links under Actions to see the following: The first