Actionscript Error Handling
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[Hide]Introduction to error handling Common error-handling tasks Important concepts and terms Working through in-chapter examples Introduction to error handlingA run-time error is something that goes wrong in your ActionScript code that flex error handling stops the ActionScript content from running in Adobe® Flash® Player or Adobe® AIR™. javascript error handling To ensure that your ActionScript code runs smoothly for users, you must write code in your application that handles the flash error handling error—that fixes it, works around it, or at least lets the user know that it’s happened. This process is called error handling. Error handling is a broad category that includes responding to many
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kinds of errors that are thrown during compilation or at run time. Errors that happen at compile time are often easier to identify—you must fix them in order to complete the process of creating a SWF file. This chapter doesn’t discuss compile-time errors; for more information on writing code that doesn’t contain compile-time errors, see ActionScript language and syntax and Object-oriented programming in ActionScript. This applescript error handling chapter focuses on run-time errors. Run-time errors can be more difficult to detect, because in order for them to occur the erroneous code must actually be run. If a segment of your program has several branches of code, like an if..then..else statement, you must test every possible condition, with all the possible input values that real users might use, in order to confirm that your code is error-free. Run-time errors can be divided into two categories: program errors are mistakes in your ActionScript code, such as specifying the wrong data type for a method parameter; logical errors are mistakes in the logic (the data checking and value manipulation) of your program, such as using the wrong formula to calculate interest rates in a banking application. Again, both of these types of errors can often be detected and corrected ahead of time by diligently testing your application. Ideally, you’ll want to identify and remove all errors from your application before it is released to end users. However, not all errors can be foreseen or prevented. For example, suppose your ActionScript application loads information from a particular website that is outside of your control. If at
in an application Contents [Hide]Using try..catch..finally statements The throw statement Displaying a simple error message Rethrowing errors The most common error handling is synchronous error-handling logic, where you insert statements into your code to catch synchronous errors at run actionscript error 2060 time. This type of error handling lets your application notice and recover from run-time
Actionscript Error 1009
errors when functions fail. The logic for catching a synchronous error includes try..catch..finally statements, which literally try an operation, catch any
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error response from Flash Player or Adobe AIR, and finally execute some other operation to handle the failed operation. Using try..catch..finally statementsWhen you work with synchronous run-time errors, use the try..catch..finally statements to catch errors. http://help.adobe.com/en_US/ActionScript/3.0_ProgrammingAS3/WS5b3ccc516d4fbf351e63e3d118a9b90204-7ebd.html When a run-time error occurs, Flash Player or Adobe AIR throws an exception, which means that it suspends normal execution and creates a special object of type Error. The Error object is then thrown to the first available catch block. The try statement encloses statements that have the potential to create errors. You always use the catch statement with a try statement. If an error is detected in one of the http://help.adobe.com/en_US/ActionScript/3.0_ProgrammingAS3/WS5b3ccc516d4fbf351e63e3d118a9b90204-7ed1.html statements in the try statement block, the catch statements that are attached to that try statement will execute. The finally statement encloses statements that will execute whether or not an error occurs in the try block. If there is no error, the statements within the finally block execute after the try block statements complete. If there is an error, the appropriate catch statement executes first, followed by the statements in the finally block. The following code demonstrates the syntax for using the try..catch..finally statements: try { // some code that could throw an error } catch (err:Error) { // code to react to the error } finally { // Code that runs whether or not an error was thrown. This code can clean // up after the error, or take steps to keep the application running. } Each catch statement identifies a specific type of exception that it handles. The catch statement can specify only error classes that are subclasses of the Error class. Each catch statement is checked in order. Only the first catch statement that matches the type of error thrown will execute. In other words, if you first check the higher-level Error class and then a subclass of the Error class, only the higher-level Error class will match.
Home ArticlesBest Practices Exceptions and Exception Handling Exceptions and Exception Handling Email to Friend Print Article Remove from Favorites Add to Favorites Remove from 'Articles http://www.actionscript.org/resources/articles/603/8/Exceptions-and-Exception-Handling/Page8.html to Read' Add to 'Articles to Read' ByColin Moock | Published http://stackoverflow.com/questions/3455577/in-flash-as3-how-to-put-single-try-catch-code-in-order-to-catch-any-errors-in-w May 18, 2007 | Best Practices , Intermediate | Rating: Unrated Exception Bubbling Copyright © 2004 O'Reilly Media, Inc. All Rights Reserved. Essential ActionScript 2.0By Colin MoockJune 2004ISBN: 0-596-00652-7More info... . Available from booksellers or direct from O'Reilly Media, www.oreilly.com. This content is excerpted error handling from the above-named O'Reilly publication, with permission, by agreement with ActionScript.org. Earlier we learned that exceptions in a try block can be thrown either directly or as the result of a method call. In reality, an exception can be thrown anywhere in an ActionScript program, even on a frame in a timeline! Given that an exception actionscript error handling can be thrown anywhere, how does the ActionScript interpreter find the corresponding catch block to handle it? And what if no catch block exists? These mysteries are resolved through the magic of exception bubbling. Let's follow along a bubbly ride with the ActionScript interpreter as it encounters a throw statement in a program. During the following dramatization, the interpreter's musing are shown in code comments. When a throw statement executes, the interpreter immediately stops normal program flow and looks for an enclosing try block. For example, here's a throw statement: // INTERPRETER: Hmm. A throw statement.// Is there an enclosing try block for it?throw new Error("Something went wrong"); If the throw statement is enclosed in a try block, the interpreter next tries to find a catch block whose parameter's datatype matches the datatype of the value thrown (in the present case, Error): // INTERPRETER: Great, I found a try block. Is there a matching catch block?try {throw new Error("Something went wrong");} If a matc
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up In flash AS3 How to put single try catch code, in order to catch any errors in whole class? up vote 2 down vote favorite 3 In Flash AS3 I wanna write the single try catch block in order to catch any errors in whole class. For example, I have a lot of functions in myClass.as. I don't wanna write in each function try catch blocks in order to catch errors in this function. Is there any methods to do this? Thank you! actionscript-3 flash try-catch throw share|improve this question edited Feb 6 '13 at 19:26 asked Aug 11 '10 at 5:50 Almas Adilbek 2,15083980 add a comment| 2 Answers 2 active oldest votes up vote 5 down vote accepted you can't! there is no such easy way like that even in other language either than AS3 except they use AOP approach to do that. The best practice is just let you classes bubble the Error (Exception) and let the higher layer catch and process the error. EDIT - regarding coment Actually the idea is the natural way.. still you need to manually catch every possible error. i'll give you example. Note that the purpose of the example only for clarity between lower layer and higher layer. for example you have a class in the mid layer (Your Business Process): public class MyBussiness { public function loadImages(){ //for example here is a block of method //possibly throws exception. } public function getLoan(){ //lets assume here too } } in the higer layer (I Assume in your View - MXML) you catch the exception like bellow: var myBussiness:MyBussiness = new MyBussiness(): try { myBussiness.loadImages(); //any other sequence process myBuss