try-catch

问题 I want to write trycatch code to deal with error in downloading from the web. url <- c( "http://stat.ethz.ch/R-manual/R-devel/library/base/html/connections.html", "http://en.wikipedia.org/wiki/Xz") y <- mapply(readLines, con=url) These two statements run successfully. Below, I create a non-exist web address: url <- c("xxxxx", "http://en.wikipedia.org/wiki/Xz") url[1] does not exist. How does one write a trycatch loop (function) so that: When the URL is wrong, the output will be: "web URL is

问题 Recently I've encouraged weird error in PHP code. It's like the inner try{}catch(){} block is omited when using PDOStatement object with foreach(){} . Here is my test code which triggers this behaviour: <?php /* // THIS WORKS AS EXPECTED, JUST UNCOMMENT try{ for($i = 0; $i < 3; $i++){ try{ echo "\nTHROWING EXCEPTION\n\n"; throw new Exception("AAAAAAAAAAAAAAAAAAAAAAAAA"); echo "EXCETION THROWN (SHOULD NOT SHOW)\n"; }catch(Exception $err){ echo "========= INNER CATCH =========\n"; echo $err-

问题 I got this code: try { using (SqlConnection sourceCnx = new SqlConnection(SOURCE_CONN_STRING)) { sourceCnx.Open(); SqlCommand sysCmd = sourceCnx.CreateCommand(); sysCmd.CommandText = "My query"; sysCmd.ExecuteNonQuery(); } } catch (Exception) { //Throwing a message box informing that there is an error } I want to display a message when the user is no longer connected to the internet. But when I debug my program without an internet connection, the program crashes with a SqlException. (The

问题 I was running some code & I wasn't getting any errors, but the row wasn't being deleted either.... so I was a bit confused. So I checked out the code & found out I had a problem with my query, but at the same time it wasn't producing a true result to my test with mysql_error(). I am using the below code.. try { // Start transaction beginTransaction($this->db_connection); } catch (Exception $e) { throw new Exception($e->getMessage()); } try { // Delete main entry $this->removeMainEntry($lid);

问题 I am trying to parse a date/time json from server side inside bind viewholder. The date string am trying to parse is this: 2018-06-25T08:06:52Z Here is the code that I am using ( got it from another stack overflow thread) try { SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.ENGLISH); df.setTimeZone(TimeZone.getTimeZone("Africa/Nairobi")); Date date = df.parse(timeToConvert); df.setTimeZone(TimeZone.getDefault()); String formattedDate = df.format(date); String

问题 I just learned about exception handling. So, I am still getting use to it. I know how to do the basic exception handling like entering in a correct value for division and having it throw a DividebyZeroException if a incorrect value is entered. But I need help some help on doing the following: Create an exception handling to throw an error if 1) The number of integer in each row are not equal to each other for example: Matrix = [ 3 4; 9 8 1] should be : matrix = [ 3 4 2; 9 8 1] 2) the

问题 While on return to my app from getting phone number from address book, if by mistake i fetch some address or any thing except for phone number, the code in the try catch final gives the following but doesn't catch it, any idea is appreciated in advance: *** -[CFDictionary length]: message sent to deallocated instance 0x6a4db70 Code: strContact = (NSString *)phone; CFRelease(phone); // NSLog(@"%@", strContact); CFRelease(multi); name = (NSString *)ABRecordCopyValue(person,

问题 I'm wondering if I can put a try catch about $application->bootstrap()->run(); that will catch pdo exceptions This works, but it catches every exception, which I do not want. try { $application->bootstrap()->run(); } catch (Exception $e) { print_r($e); } I had a nasty incident of pdo exception being throw and displaying the password from application.ini! Worthy of note, I have tried PDOException, it doesnt get catched. My DB is set up in bootstrap run() with try { $db = $this-

问题 How do I do Exception handling in Spark - Scala for invalid records Here is my code: val rawData = sc.textFile(file) val rowRDD = rawData.map(line => Row.fromSeq(line.split(","))) val rowRDMapped = rowRDD.map { x => x.get(1), x.get(10) } val DF = rowRDMapped.toDF("ID", "name" ) Everything works fine if the input data is fine, If I dont have enough fields, I get ArrayIndexOutOfBoundException. I am trying to put try-catch around, but I am not able to skip the records with invalid data, via try

问题 I am struggling with the instructions for tryCatch() in R. I'm trying to capture the closing price for a ticker. Case 2 = good case = TickersJuly2 = unique price to ticker relationship Case 1 = bad case = TickersJuly1 = FABU close price is the repeat of CETX Case 1 desired output is a 0 for FABU. library(TTR) close.price1=NULL TickersJuly1 <- c('DIT','CETX','FABU') TickersJuly2<- c('AAPL','A','AA') for(i in TickersJuly1){ tryCatch(close <- getYahooData(i,20150727,20150727,'daily',"price"),