try-catch

问题 Im writing a program for homework where I need to validate user input and then create an object and add it to an array list. i have included just what i think is the relevant code, but im a beginner for sure so let me know if there is something else you need to see. I have the user enter a string, then check to see if its a double. if its not a double, i throw an exception that i created try{ price = Double.parseDouble(strPrice); } catch(NumberFormatException nfe){ CDException cde = new

问题 How can I not get the right syntax for a simple try/catch? Do I have to do anything more? All I get is error 1064... BEGIN TRY SELECT * FROM NonExistentTable; END TRY BEGIN CATCH SELECT * FROM ExistingTable; END CATCH; GO #1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'TRY SELECT * FROM NonExistentTable' at line 1 Thanks 回答1: MySQL doesn't have TRY/CATCH functionality. You can use handlers. 来源：

问题 How does the catch keyword determine the type of exception that was thrown? What process occurs to select which catch block to execute? try { int[] myArray = new int[0]; myArray[1] = 0; } catch (IndexOutOfRangeException ex) { } // how does the CLR know to enter here? catch (InvalidCastException ex) { } Via ILdasm .method private hidebysig static void Main(string[] args) cil managed { .entrypoint // Code size 28 (0x1c) .maxstack 3 .locals init (int32[] V_0, class [mscorlib]System

问题 This question already has answers here : Try-Catch doesn't show Message Dialog box with await (1 answer) Better way to show error messages in async methods (2 answers) Await in catch block (9 answers) Closed 6 years ago . I am using the following code in my Windows 8 app function to catch an error and display an Message Dialog catch (Exception ex) { MessageDialog err = new MessageDialog("Error"); await err.ShowAsync(); } But I get an error "cannot await in the body of a catch clause". But

问题 On my XAMPP/Win XP build, PHP5.2.3 fails to catch any exceptions. None of the examples work, and this: try { throw new Exception('Fail'); } catch (Exception $e) { echo 'Succeed'; } ...results in: Fatal error : Uncaught exception 'Exception' with message 'Fail' in M:\path\to\test.php:4 Stack trace: #0 {main} thrown in M:\path\to\test.php on line 4 All of PHP's error settings seem standard. Server is Apache/2.2.4 回答1: This depends on eAccelerator's build in XAMPP. At one point, it had trouble

问题 I have the following code which gives me an " Exception was unhandled by user code " when it tries to throw an error: private static void _msgQ_RecieveCompleted(object sender, ReceiveCompletedEventArgs e) { try { //queue that have received a message MessageQueue _mq = (MessageQueue)sender; //get the message off the queue Message _mqmsg = _mq.EndReceive(e.AsyncResult); throw new Exception("This is a test exception by Tim"); //set the values back into a formatted struct //now process your SQL..

问题 In my application, I have a food activity in which the user enters his/her food, and the app requests the food, by the name entered by the user, from a MYSQL database. In the case that the entered food not exist, the string returned by the database should be null. Currently, when this happens, an exception to occurs since the null value cannot be parsed to a JSON array. My question is: "Is there a way to prevent my app from force closing? Can I handle the exception and display a toast

问题 We use sp_send_dbmail to notify us of certain problems and sometimes we attach files to the emails. Occasionally we will get an Error 32 (file in use) error. I've put some code together to send the email without the attachment in this situation but no matter what I do I'm unable to CATCH the error and ignore it. I'd like to be able to handle or ignore any errors from sp_send_dbmail because this causes a job failure in production. I tried implementing the technique described in this article

问题 I resolve a problem which was showing up no compatibility on Edge but in Chrome. So, I changed using Object.assign(a, {}) instead of {...a, {}}. Here's where I discussed this previous problem: I would like to know why my website is not showing up on Edge? it's developed on JavaScript But, later I got another error. And let me explain you. It's this one on the console: SCRIPT1005: Expected '('. This error appears just on Edge browser. main.load = function (page) { function getClass(className)

问题 I am tring to count the number of exceptions happening and log those exceptions as well. So what I did is, I created one method addException in which I am counting all the exceptions. addException method accepts two parameters, one is the String , and other is the boolean flag which means whether we want to terminate the program or not because of any exceptions. Meaning, if that flag is true, then I need to terminate the program whenever there are any exceptions. So if you take a look into my