exception-handling

问题 using(SomeClass x = new SomeClass("c:/temp/test.txt")) { ... } Inside the using block, all is fine with treating exceptions as normal. But what if the constructor of SomeClass can throw an exception? 回答1: Yes , this will be a problem when the constructor throws an exception. All you can do is wrap the using block within a try/catch block. Here's why you must do it that way. using blocks are just syntactic sugar and compiler replaces each using block with equivalent try/finall block. The only

问题 Using Java (android but this is a java question ) i have created a default exception handler in the application class like this more or less which was taken from some SO thread: public class MyApplication extends Application { @Override public void onCreate() { super.onCreate(); AppInitialization(); } private void AppInitialization() { defaultUEH = Thread.getDefaultUncaughtExceptionHandler(); Thread.setDefaultUncaughtExceptionHandler(_unCaughtExceptionHandler); } private

问题 Using Java (android but this is a java question ) i have created a default exception handler in the application class like this more or less which was taken from some SO thread: public class MyApplication extends Application { @Override public void onCreate() { super.onCreate(); AppInitialization(); } private void AppInitialization() { defaultUEH = Thread.getDefaultUncaughtExceptionHandler(); Thread.setDefaultUncaughtExceptionHandler(_unCaughtExceptionHandler); } private

问题 I have a few doubts regarding exception handling in iPhone. Here are they: Suppose I have a chain of methods which are being called one after the other, that is, method A calls method B, which in turn calls method C, which calls method D. Which is the best place to put my try-catch block (is it method A or B or C or D or all of them). Also, I need to display an alert to user that an exception has occured and then, I want to log this exception to my server. So, if I am writing my try - catch

问题 Very simply put, I am wondering if anybody here can give me an example of a user-defined exception in VB.Net. I already have two examples that I was able to find online, but other than that, I cannot think of any more. I need to find at least 5 to put in my notes, and then submit to my teacher. The two I have so far are: invalid login information (such as improper username or password), and expired credit card information on an online store. Any help would be greatly appreciated. 回答1: The

问题 I have an exception that is produced at ~20 seperate places. It can be rescued easy and in the same way at every place but thats not dry and eaven a crapy work! I want to rescue this exception at a central position. How can I arrange this? Its about the ActiveRecord::RecordNonUnique exception by the way,... 回答1: What about this ? def rescue_from_record_non_unique yield rescue ActiveRecord::RecordNonUnique # your code end # ... rescue_from_record_non_unique do # do something end 来源： https:/

问题 I have the following code where a variable is being initialized with the result of a function call. This function throws so I set up a try-catch to catch the exception. For some reason the exception is still showing up on the screen even after the catch clause runs. #include <iostream> #include <stdexcept> int f() { throw std::invalid_argument("threw"); return 50; } struct S { S() try : r(f()) { std::cout << "works"; } catch(const std::invalid_argument&) { std::cout << "fails"; } int r; };

问题 I have the below code with which i am able to print the fullclassname,classname,methodname, at which error occured. Also, I am able to print Line-Number but the Line-Number printed is the line at which the variable "LineNumber" is initialized. How can i print the exact LineNumber and ColumnNumber in try block at which error occured? try { SQL Query } catch(Exception e) { String fullClassName = Thread.currentThread().getStackTrace()[1].getClassName(); String className = fullClassName.substring

问题 I have a script with an exception handler. This exception handler cleans up a couple connections, prior to the script exiting after an exception. I would like to re-throw the exception from this exception handler so that it is handled by PHP's own last-resort exception handler, where the error is written to PHP's error log, or whatever the default is, as configured in PHP.ini. Unfortunately, this doesn't seem like a possibility, as outlined here: http://www.php.net/manual/en/function.set

问题 In PHP, how do variable scope rules apply to Try/Catch blocks? Do variables declared within the try block go out of scope when the block has finished? Or are they in scope until the end of the function/method? For example: try { // This may throw an exception when created! $o = new Pronk(); } catch (Exception $ex) { // Handle & exit somehow; not important here return false; } $o->doPronk(); Is this valid? Or should $o = NULL; be set before the try/catch to keep $o in scope? (I know that the