try-catch

问题 I've got a complicated, long function that I'm using to do simulations. It can generate errors, mostly having to do with random vectors ending up with equal values with zero-variance, getting fed either into PCA's or logistic regressions. I'm executing it on a cluster using doMC and plyr . I don't want to tryCatch every little thing inside of the function, because the possibilities for errors are many and the probabilities of each of them are small. How do I tryCatch each run, rather than

问题 I have a list of multiple xml files which have the same structure. Some of them have structural errors in them so they can't be read, i'm not capable of controlling them manually because there are too many files. I know that i need to imply the try or trycatch functions, i tried to understand them but i'm not understanding how to use them proberly on my case. To make the example easy i just want to transform them all into a csv. library(XML) k <- 1 Initial.files<- list.files("/My/Initial

问题 I have quite a complex express route in my node.js server, that makes many modifications to the database via mongoose . My goal is to implement a mechanism, that reverts all changes when any error occurs. My idea was implementing functions for undoing into the catch block. But this is quite ugly, as I have to know what the previous values were and what if an error occurs in the catch block? It's especially difficult to revert those changes, when an error occurred during a Promise.all(array

问题 I have two versions of Java code that gets user input until user types "q" Version 1: public class Test { public static void main(String[] args) { String input = ""; while (!input.equals("q")) { Scanner scanner = new Scanner(System.in); System.out.print("Input: "); input = scanner.nextLine(); System.out.println("Input was: " + input); } } } Version 2: public class Test { public static void main(String[] args) { String input = ""; while (!input.equals("q")) { try(Scanner scanner = new Scanner

问题 I am using the debugger (vs2008). Once I've stepped into a catch statement, I would like to know if there is any way to set the execution cursor back to the beginning of the try. Just dragging it there doesn't seem to work, is there some setting I need to change? Example: try { //Want the cursor back here } catch { //some code, cursor is here... } 回答1: Apparently it depends which flavor of .NET runtime you are using. At the time I first wrote this, it worked fine for me when I tried it, but I

问题 Why in the following code TRY didn't catch the error and how can I catch this error? BEGIN TRY BULK INSERT [dbo].[tblABC] FROM 'C:\temp.txt' WITH (DATAFILETYPE = 'widechar',FIELDTERMINATOR = ';',ROWTERMINATOR = '\n') END TRY BEGIN CATCH select error_message() END CATCH I just get this: Msg 4860, Level 16, State 1, Line 2 Cannot bulk load. The file "C:\temp.txt" does not exist. 回答1: This is one option that helps to catch this error: BEGIN TRY DECLARE @cmd varchar(1000) SET @cmd = 'BULK INSERT

问题 I'm getting an error: "TypeError: item.setAttribute is not a function" when I try to call the following function on my webpage: function list() { var colors = document.getElementById('colors'); var colors = colors.childNodes.length; for (var i = 1; i < broj; i++) { var item = colors.childNodes.item(i); item.setAttribute("id", i); item.setAttribute("onmouseover", "moveover(src)"); item.setAttribute("alt", "Color"); item.hspace = "2"; item.height = "23"; } } function moveover(colorAddress) {

问题 I have a thread in which I catch all errors in a big, all-encompassing catch block. I do this so that I can report any error, not just expected ones, in my application. My Runnable looks like this: public final void run() { try { System.out.println("Do things"); /* [1] */ doUnsafeThings(); } catch (Throwable t) { System.out.println("Catch"); /* [2] */ recover(); } finally { System.out.println("Finally"); /* [3] */ } } I would expect the NPE to be caught by the Throwable catch block. Instead,

问题 I have a section in my code where I am querying all SQL Server Databases on my network. I am first trying to use a SQL Login to access the SQL Server Instance but if that fails then I want to try connecting using my Windows Credentials. After that if I still can't connect then I want the code to fail and then notify the user. So I guess what I am asking is how can I loop back from inside of a Try-Catch block to the line just above the Try-Catch block: String conxString = @"Data Source

问题 try: commands try: commands try: commands try: commands except: commands return to final commands except: commands return to final commands except: commands return to final commands except: commands final commands Which instruction have I to write in place of return to final commands to make that any except returns to the top-level instructions following the outer try? And is it an acceptable structure? Edit: Here is a toy example (I know I can do it using if s, it's only an example; suppose