try-catch

问题 Currently scraping a page which can have a variable amount of elements and also sometimes formats the same data elements with different selectors. Currently trying to ignore errors thrown by RSelenium with some tryCatch code but still stops when the specified element is not on the page: result <- tryCatch({ webElem <- remDr$findElement('xpath', "//tr[(((count(preceding-sibling::*) + 1) = 9) and parent::*)]//span[(((count(preceding-sibling::*) + 1) = 1) and parent::*)]") }, warning = function

问题 I'm trying to implement a try-catch block in scheme using (call-cc) method but i'm not sure how it can be used for that. I could not find any example. And found examples contains just error-handling but what i want to do is: if an error occurred, the scheme program has to give a message to user (via display for-example) without suspending the program. Is that possible? 回答1: Since you want to catch all errors, such as ones raised by both raise and raise-continuable you'd need both an exception

问题 I'm trying to implement a try-catch block in scheme using (call-cc) method but i'm not sure how it can be used for that. I could not find any example. And found examples contains just error-handling but what i want to do is: if an error occurred, the scheme program has to give a message to user (via display for-example) without suspending the program. Is that possible? 回答1: Since you want to catch all errors, such as ones raised by both raise and raise-continuable you'd need both an exception

问题 I am using a REST service to generate a CSV file that I want to prompt the user to download. An example of the service is below: https://localhost:8444/websvc/exportCSV?viewId=93282392 To prompt the user to download the file, I use this code: window.location.href = exportUrl , where exportUrl would be a URL like the one above. This works great if there are no errors on the server when executing the service. The file download prompt appears, the page doesn't refresh, and all is well. However,

问题 I am using a REST service to generate a CSV file that I want to prompt the user to download. An example of the service is below: https://localhost:8444/websvc/exportCSV?viewId=93282392 To prompt the user to download the file, I use this code: window.location.href = exportUrl , where exportUrl would be a URL like the one above. This works great if there are no errors on the server when executing the service. The file download prompt appears, the page doesn't refresh, and all is well. However,

问题 When I type warnings() to console, I get back Warning message: In fread(my_directory, ... : C function strtod() returned ERANGE for one or more fields. The first was string input '4.40589099726375E-309'. It was read using (double)strtold() as numeric However when I type as.character(warnings()) , I get: [1] "fread(my_directory)" My objective is to get the actual message displayed in warning() into a character string, so that I can pass it to the logwarn function in the logging package.

问题 I have a problem. I need write a C# program Input: Allows the user to enter multiple lines of text, press Ctrl + Enter to finish typing Output: Standardize by, rearranging lines in the right order of increasing time. I was tried but I don't know how to catch Ctrl + Enter from keyboard: I expect the output like Example: “Created at 28/02/2018 10:15:35 AM by Andy. Updated at 03/03/2018 02:45:10 PM by Mark Clear name at 02/03/2018 11:34:05 AM by Andy” DateTime is needed rearranging 回答1: You need

问题 I am very new to RSelenium. I have a list of Finnish companies and I would like to extract the corresponding Business ID on the web page https://tietopalvelu.ytj.fi/yrityshaku.aspx?kielikoodi=3 A simple version of my R-code is the following: library(RSelenium) name_company <- c("nokia", "test") driver <- rsDriver(browser= 'firefox', port = 16L) remote_driver <- driver[["client"]] remote_driver$navigate("https://tietopalvelu.ytj.fi/yrityshaku.aspx?kielikoodi=3") input1 <- remote_driver

问题 I have this for loop that download a json file from a solr search server. It loops over a vector that contain keywords (100, in this case): library(jsonlite) for (i in 1:100) { docs <- fromJSON(paste("http://myurl.com/solr/select?df=topic&fq=",keywords[i],"&indent=on&q=*:*&rows=1&wt=json",sep="")) numFound <- docs$response$numFound print(numFound) } It works fine, until it reaches a certain keyword that is not found on the solr, and returns this error: Error in open.connection(con, "rb") :

问题 I'm trying the newly implemented try/catch statements which are available since TwinCAT 4024.0. However, I'm getting the following error when compiling: The codegenerator for the current device does not support structured exception handling. Example code (source): FUNCTION F_Calc : LREAL VAR_INPUT pData : POINTER TO ARRAY [0..9] OF LREAL; nElementA : INT; nElementB : INT; END_VAR VAR exc : __SYSTEM.ExceptionCode; END_VAR __TRY F_Calc := pData^[nElementA] / pData^[nElementB]; __CATCH (exc) IF