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Exceptions

exceptions

Great Reads

Much Ado About NULL

by Giovanni Scerra

Patterns to prevent null reference exceptions

Continued code execution after (throwing) an Exception

by Jasper Lammers

A method to easily toggle the way exceptions are being handled (either being thrown or handled by custom code), while still conserving the stack trace when exceptions are not being thrown.

A Quick and Dirty Extension Method to Get the Full Exception Details, Including Inner Exceptions

by Marco Bertschi

This tip presents an easy way of verbosely converting an exception and its inner exceptions to a string in order to get access to all details.

Exception: Configuration System Failed to Initialize [With Solution]

by Amogh Natu

This tip provides one solution to the exception "Configuration system failed to initialize" in C#

Latest Articles

Task EventHandlers – The Little Secret You Didn’t Know

by Dev Leader

Secret of Task EventHandlers

Application Crashes without a Trace / No Dumpfile

by Bruno van Dooren

Symantec can cause valid applications to crash and be gone without a trace

C# DataAdapter returning Exception “Failed to enable constraints.”

by Mark Pelf

We explain how to debug and get more information on the generic Exception “Failed to enable constraints.”

Robust C++: Safety Net

by Greg Utas

Keeping a program running when it would otherwise abort

All Articles

Exceptions

How to disable or enable exceptions

27 Nov 2023 by Mircea Neacsu

You might try to use my error code objects. They are a cross between exceptions and error codes. See C++ Error Handling with Error Code Objects[^]. Latest version of code can be downloaded from GitHub - neacsum/mlib: Multi-Purpose Library[^]

How to disable or enable exceptions

25 Nov 2023 by Code_bro

Hi, i like to make my class working with exceptions or if needed not working with exception. I like to make them switchable. I made a serial port class and it throws me exceptions as i need. But when i choose to not use them how can i get this...

C# export logs to 2 txt files

24 Nov 2023 by PinkGoat_

So I have a button made from my xaml file (view), called Export. When the user clicks on it, the logs created during the run of the app get exported to Logs.txt. If there are Warnings, Errors or Exceptions, those will instead be created in...

C# export logs to 2 txt files

24 Nov 2023 by Graeme_Grant

The best solution, IMHO, would be to create a custom log provider. You can then handle the logging as the log entries are added. I wrote an article for a custom Log Viewer control that has a custom Log Provider, one for each of the 4 common...

Task EventHandlers – The Little Secret You Didn’t Know

19 Feb 2023 by Dev Leader

Secret of Task EventHandlers

Predefinied exception vs exception class

10 Feb 2023 by FosanzDev

I was defining a new type of Exception to 'replace' IndexOutOfBounds exception. In first instance I defined a new Class: public class NoNextItemException extends Exception { public NoNextItemException(String message) { ...

Predefinied exception vs exception class

10 Feb 2023 by Richard MacCutchan

public double peek() throws NoNextItemException { That statement tells Java that the peek method may throw the NoNextItemException. But since this is a Throwable exception, it must be caught in any methods that include a call to peek. When you...

Design a class reserveticket with an instance variable seatsavailable, and a method void reserve ( int numberofseats).

27 Jan 2023 by Arnaav PL

Design a class ReserveTicket with an instance variable seatsavailable, and a method void reserve ( int numberofseats). If `numberofseats' is greater than `seatsavailable' then throw a user defined exception SeatFullException otherwise throw a...

Design a class reserveticket with an instance variable seatsavailable, and a method void reserve ( int numberofseats).

27 Jan 2023 by Richard MacCutchan

Quote: i am new to java and idk how to do this Then the first thing you need to do is to go and learn it from the ground up: Java Tutorials Learning Paths[^]

Design a class reserveticket with an instance variable seatsavailable, and a method void reserve ( int numberofseats).

27 Jan 2023 by OriginalGriff

While we are more than willing to help those that are stuck, that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for...

Sign file and classnotfound error while compiling a sample with intellij idea

8 Jan 2023 by reverser69

hi all i have a target app written in Java. i want to call one of its functions. im using Intellij Idea. i imported its dependencies. wrote a few lines of code and till now, i have two problems. 1. i get: Exception in thread "main"...

Sign file and classnotfound error while compiling a sample with intellij idea

8 Jan 2023 by Richard MacCutchan

1. See the discussion at https://stackoverflow.com/questions/34855649/invalid-signature-file-digest-for-manifest-main-attributes-exception-while-tryin[^]. 2. The log4j library is not part of a the standard Java libraries, so you need to include...

Application Crashes without a Trace / No Dumpfile

7 Sep 2022 by Bruno van Dooren

Symantec can cause valid applications to crash and be gone without a trace

C# DataAdapter returning Exception “Failed to enable constraints.”

15 Jul 2022 by Mark Pelf

We explain how to debug and get more information on the generic Exception “Failed to enable constraints.”

Robust C++: Safety Net

27 Jun 2022 by Greg Utas

Keeping a program running when it would otherwise abort

Of Threads and Objects

17 Jun 2022 by Mircea Neacsu

C++ thread objects and their use

How to manage finally block in API when we have custom exception filter enabled?

25 May 2022 by Ravi-from-India

Hello, I have an API in which I have implemented custom exception filter. so, basically I don't have try/catch block in my controller. Just customErrrorAtrribute is there in my controller. Normally, I write code for my database connectivity...

How to manage finally block in API when we have custom exception filter enabled?

25 May 2022 by Richard Deeming

Always wrap disposable objects such as SqlConnection / SqlCommand in using blocks. That way, they will always be disposed of properly. Eg: using (SqlConnection con = new SqlConnection("connection string")) using (SqlCommand cmd = new...

How to manage finally block in API when we have custom exception filter enabled?

25 May 2022 by lmoelleb

You have moved the small peace of code reporting any exception as an API Json object (or whatever you use) - anything else related to try/catch/finally blocks should still remaining where it is. So you still need try/finally blocks to ensure...

How do I resolve a java.lang.arrayindexoutofboundsexception when my array is null?

21 May 2022 by Temba Lumbuka Mwamba

I keep receiving Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 4 out of bounds for length 4 at covid19.Covid19.main(Covid19.java:70) but the array I used is null so it shouldn't have a specified length What I have...

How do I resolve a java.lang.arrayindexoutofboundsexception when my array is null?

21 May 2022 by OriginalGriff

We have no idea which lin e is line 70 - from the error message: Index 4 out of bounds for length 4 at covid19.Covid19.main(Covid19.java:70) So the first thing you need to do is work out which line it is. Most editors support CTRL+G to go...

Why is ruby throwing me unexpected end of input

12 May 2022 by Tyrunt.new("Rix")

Oh, I just needed to add `end` in the `stick(place)` function!

Why is ruby throwing me unexpected end of input

12 May 2022 by Tyrunt.new("Rix")

Hello, coding guys, As you saw in the title, Ruby is throwing me: main.rb:59: syntax error, unexpected end-of-input, expecting `end' and, this is my code: # Logging puts "Hello, world!\n" # Input getting & variables puts "What is your name?"...

How do I resolve an inputmismatchexception from user whilst using the java try with resources feature

17 Mar 2022 by Cameron Grant 2021

I've found that if I use the try with resources feature java provides which will automatically close of resources, I then can't use a boolean flag (or recursion) to resolve an InputMismatchException within a try catch as the catch block seems to...

How do I resolve an inputmismatchexception from user whilst using the java try with resources feature

17 Mar 2022 by Richard MacCutchan

The Scanner object only exists within the try block, so you cannot refer to it in the catch. And you specifically should not be doing so. You should rework the code so that the Scanner is instantiated before the try, and is not referred to in the...

Succeed in getting voice to read text

13 Mar 2022 by Cameron Grant 2021

I am trying to work out how to implement text to speech with java 11 and have written some classes in order to read a text ("Dracula") and then and option to speak the text. Classes: package draculatext; import java.io.BufferedReader; import...

Succeed in getting voice to read text

13 Mar 2022 by Richard MacCutchan

The error message is telling you that the system cannot find the VoiceManager, which suggests that it is not aware of the location of the jar file(s). Make sure that the file's location is passed to the virtual machine by adding it as follows: ...

Lintosql convert to entity framework dbcontext errors

17 Feb 2022 by Roger Burke

Hi got a project that used LinqToSQL for database access and is now being converted to Entity Framework Core. Most conversions are ok but have come across this one that I am having trouble with...what happens if you have a db conflict on save....

entity-framework

Lintosql convert to entity framework dbcontext errors

17 Feb 2022 by Richard Deeming

Handling Concurrency Conflicts - EF Core | Microsoft Docs[^] Tutorial: Handle concurrency - ASP.NET MVC with EF Core | Microsoft Docs[^]

entity-framework

Type of expression is ambiguous without more context

11 Jan 2022 by Member 15127345

I'd like to iterate through the tuple in a for loop, like this: for i in 0...4{ if let value = element.list_of_keywords?.i, value == keyword { if let value = element.name{ returnListOfCities(name: value) ...

Java.lang.nullpointerexception: attempt to invoke virtual method on a null object reference

2 Jan 2022 by Member 15127345

The issue was in the second constructor. I had to change one line of code. constructor(resourceId: Int): this(resourceId, false) Reason why I had to do this: I was calling another constructor, but I wasn't saving values back to the Stage class...

Java.lang.nullpointerexception: attempt to invoke virtual method on a null object reference

2 Jan 2022 by Member 15127345

I'm writing an app in Kotlin, which displays 2D object on user's phone. When I execute my code, I get Java.lang.nullpointerexceptionRun. Sadly, I don't know how to fix this issue. Run output: E/com.a3dmodelap: Invalid ID 0x00000000....

Java.lang.nullpointerexception: attempt to invoke virtual method on a null object reference

2 Jan 2022 by 0x01AA

How is about to check wheter val bmp = BitmapFactory.decodeResource(context.getResources(), resourceId, opts) returns a 'not null' value? And in case it returns null you need to investigate why...

Java.lang.nullpointerexception: attempt to invoke virtual method on a null object reference

2 Jan 2022 by Luc Pattyn

it looks like bmp is null due to resourceId being zero. And you did not show any code that sets resourceId...

Using without if else statement how to avoid nullpointerexception in java

29 Nov 2021 by Member 15435322

This is my method, which I am using Optional to avoid NullPointerException, but I want to do that using without if else statement to avoid nullpointer exception. is it possible or is there any way, that I say using without if else statement...

Using without if else statement how to avoid nullpointerexception in java

29 Nov 2021 by OriginalGriff

The null checks are there for a reason - to make sure that there is a User, that the user has an Address, and the address includes a State - without these, there is no information to process - and the null return is the way the method tells you...

Skip Logfiles - Try Automated Exception Handling!

19 Nov 2021 by jgauffin

codeRR is an open source error handling service. It includes the context information that you forgot to include when you logged/reported the exception.

Already put the code with exception handling.still getting classnotfoundexception? Earlier the code was running fine, but now generating exception

14 Oct 2021 by HIMANSHU SRIVASTAVA Oct2021

```This register servlet class from where the exception is generating``` *Earlier the code was running fine on inputting fields in the page.But,after sometime it is generating this exception* package com.techblog.servlets; ...

Getting: java.nio.file.filesystemexception: C:\users\anar.memmedov\desktop\file.xlsx -> C:\users\anar.memmedov\desktop\ko\file.xlsx: the process cannot access the file because it is being used by anot

14 Oct 2021 by Dave Kreskowiak

Look at what you appear to be doing: String phoneNumber = ""; String textMessage = ""; FileInputStream excelFile = new FileInputStream(file); Path sourcePath = Paths.get(String.valueOf(file)); Path targetPath =...

Getting: java.nio.file.filesystemexception: C:\users\anar.memmedov\desktop\file.xlsx -> C:\users\anar.memmedov\desktop\ko\file.xlsx: the process cannot access the file because it is being used by anot

14 Oct 2021 by User 15041314

This is my code, which accept generally .xlsx format file and insert to database and also move accept file to my specified folder. When I trying to move it, I have getting this error: Normally, it successfully writes the received excel file to...

What is the best way to handle errors exception between application and an API?

13 Sep 2021 by wa.war

I understand that the API could be returning status codes like this:200 - OK400 - Bad Request500 - Internal Server ErrorHere is my code, how to handle the error from API in my controller?public ActionResult Get() { string token_access =...

What is the best way to handle errors exception between application and an API?

13 Sep 2021 by Oscar Valdez

IRestResponse response = client.Execute(request); if (response.StatusCode == System.Net.HttpStatusCode.OK) { } else if (response.StatusCode == System.Net.HttpStatusCode.BadRequest) { } else if (response.StatusCode ==...

Exception thrown once when using clr/cli wrapper

19 May 2021 by dj4400

Hi, I have a native c++ app. that uses a clr/cli wrapper to call a c# dll function. The solution is built in VS.2017, using the platform toolset of vs2010(v100) and includes the native c++ project, the clr/cli wrapper project and the c# dll...

Exception thrown once when using clr/cli wrapper

19 May 2021 by Dave Kreskowiak

That's not an exception. It's just a debugger message that says it cannot load the symbols from the PDB file for the wkernelbase assembly. There's nothing to worry about there. If you want to get rid of it, you can enable automatically...

The sqlparametercollection only accepts non-null sqlparameter type objects, not string objects

16 Apr 2021 by GlennAshan

I'm getting this following exception to my log file when I try to run the windows service, Exception: The SqlParameterCollection only accepts non-null SqlParameter type objects, not String objects. What should I modify to avoid this exception?...

Windows-service

The sqlparametercollection only accepts non-null sqlparameter type objects, not string objects

16 Apr 2021 by Richard Deeming

Try replacing: cmd.Parameters.Add($"@p{i}") with: Dim p As SqlParameter = cmd.CreateParameter() p.ParameterName = $"@p{i}" cmd.Parameters.Add(p)

Windows-service

The instructions for this assignment are unclear and was not given example code

12 Apr 2021 by Patrice T

Quote: The instructions for this assignment are unclear and was not given example code Since the job of programming is about creating algorithms/programs, your sentence is weird. It is like saying that you are a cook dying from starvation...

The instructions for this assignment are unclear and was not given example code

12 Apr 2021 by OriginalGriff

We are more than willing to help those that are stuck: but that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for us...

How call a function, when an exception has occured and the program has stopped

1 Mar 2021 by MehranSarrafi

Hi In the C# program, I want to call a function to screen capture and save it to the database, when an exception occurs and the program is in a stopped mode. What I have tried: Hi In the C# program, I want to call a function to screen capture...

How call a function, when an exception has occured and the program has stopped

1 Mar 2021 by MehranSarrafi

Thanks, I found out my solution and I write down here; and I hope it will be useful for others. I catch the exception with try catch block and call my function to do what I need in a new thread; and then throw the exception again with the main...

How call a function, when an exception has occured and the program has stopped

23 Feb 2021 by OriginalGriff

If your app has stopped, you can't do anything: you need your code running in order to do anything. So by that time, it;'s too late - the idea is to spot problems before they become fatal, and do something useful then; then continue or fail the...

New code. How can I display an error message if the user entered invalid input?

13 Jan 2021 by lil_mint

This is for my project. My problem is I don't know how to display an error message inside my class function code. Error message must display if the user entered a non-parenthesis character. What I have tried: open_list=['(','[','{']...

New code. How can I display an error message if the user entered invalid input?

11 Jan 2021 by Sandeep Mewara

Would suggest you to use User-Defined Exception in Python using try-except Refer: How to Define Custom Exceptions in Python? (With Examples)[^] Example from there: # define Python user-defined exceptions class Error(Exception): """Base...

C++ program to insert into table inserts into table to gives error code 0

16 Dec 2020 by Dev Parzival

bool insertIntoTable(string database,string table, string query){ cout

C++ program to insert into table inserts into table to gives error code 0

16 Dec 2020 by OriginalGriff

executeQuery returns a result set, which you are not handling - so when you try to delete everything else, it finds an open result set on the connection and fails. You use executeQuery when you want to fetch data from the DB, not add it: use...

Throw exception if stack is empty

7 Nov 2020 by Lucas Dana

Good morning, I would like to know how I can check if a stack is empty and in that case throw an exception. The idea is to have a main class, and other classes that do the tests. Thank you, Luke What I have tried: Class Stack public...

The winform process exit suddenly without catching any exception.

15 Oct 2020 by ZhaoChaoHui

There are some bugs I can't solved in My WinForm Application. My WinForm Application process exit suddenly in abnormal with low probability, and it can't catch any exception before exit. The code of WinForm Application contain this: ...

Automatic raise of exception for NaN or Infinity values

22 Sep 2020 by angusmax

I have a long sequence of calculations (using variables of type "double") where some operations might result (depending on input values) in "NaN" or "Infinity".Since I don't want to add something like the following:if ((double.IsInfinity(result)) || (double.NaN(result))) {...}after...

Exception declaration in java

16 Jul 2020 by User 14853400

why unchecked exception can be undeclared in java ? But for checked exceptions you have to declare the type. i know unchecked exception happen at runtime but how that let's you to have a choice to declare or undeclared the class type What I have...

Exception declaration in java

16 Jul 2020 by Richard MacCutchan

You cannot normally recover from Unchecked Exceptions so it is difficult for the programmer to anticipate them at code creation time. See Unchecked Exceptions The Controversy (The Java™ Tutorials > Essential Classes >...

C# Winform How to Properly Dispose Excel / Interop?

14 Jul 2020 by Rencyrence

Hello, here's the scenario:Im using datagridview to export data to Excel, after many times of exporting, i have noticed that my computer become slow, and check the Processes and i saw that there's too many Excel.exe running. What i did is I closed the Application and it removes on the...

C# Winform How to Properly Dispose Excel / Interop?

14 Jul 2020 by Member 10187249

Above all solution are correct only one thing missing, still in the background task excel empty object still run for remove that you can put below code at last: Process[] excelProcesses = Process.GetProcessesByName("excel"); foreach...

Error receiving data with NetworkStream.Read from a ClientSocket

9 Jul 2020 by saransaki08

Hi guys, When I receive data sent from one application to another application I get an error. One application acts as the server and sends data to the client that connected to the server on a particular port.I sent some information via clientsocket and at that time I got this...

Error receiving data with NetworkStream.Read from a ClientSocket

9 Jul 2020 by Member 14885591

mesmo colocando 1024 nao funcionou

How to fix COM object that has been separated from its underlying RCW cannot be used.

2 Apr 2020 by Richard Deeming

I suspect the problem is that you are storing your OleDbCommand object in a class-level field, and reusing it across methods. Change your code to create the command instance when you need it, and wrap it in a Using block, and your error will...

How to fix COM object that has been separated from its underlying RCW cannot be used.

2 Apr 2020 by lelouch_vi 2

Hello, I'm having a hard time solving this one I'm working with vs2017 and access as my database. I don't really know what happened here. I have a COMBOBOX that displays the name of all category name field from my database and from there I can...

1 exception was raised by workers: see the console for details.

30 Jan 2020 by Richard MacCutchan

java.lang.RuntimeException: Duplicate class com.unity3d.ads.BuildConfig found in modules classes.jar (:UnityAds:) and classes.jar (:unity-ads:) Duplicate class com.unity3d.ads.IUnityAdsListener found in modules classes.jar (:UnityAds:) and classes.jar (:unity-ads:) Duplicate class...

1 exception was raised by workers: see the console for details.

30 Jan 2020 by Oleg Pruh

Hi, I work in Unity 2018.4.16f1 (64-bit). Today I had to build my project in Grudle, but there is a problem. Help me as soon as possible. Please do not write much, but to understand, you can write a solution step by step. 1 exception was raised by workers: See the Console for details. ...

Unauthorizedaccessexception: access to the path "D:\" is denied.

22 Jan 2020 by phil.o

Trying to write anything at the root of a drive will be problematic on any recent Windows version; better create a directory on the D: drive and write your files in it instead.

Unauthorizedaccessexception: access to the path "D:\" is denied.

22 Jan 2020 by Oleg Pruh

Hi, I'm Oleg. Today I want to build a progect in Unity 2017.4.36f1 (64-bit) and then me in the Colsole appeared Error about UnauthorizedAccessException: Access to the path "D:\" is denied. Please HELP me with that problem. More information you can see here. UnauthorizedAccessException: Access...

Unauthorizedaccessexception: access to the path "D:\" is denied.

22 Jan 2020 by OriginalGriff

We can't help you. We don't have access to your code, or your data, or your system: so we have no idea what kind of access you are trying to get to the root of drive D:, or even that D: exists on your computer. Probably it does exist: the error message is telling you that your application (or...

Unauthorizedaccessexception: access to the path "D:\" is denied.

22 Jan 2020 by F-ES Sitecore

Ensure your account has access to the D;\ drive. If you are creating a project directly in the root of the D drive, or have anything that creates files in the root of the D drive then make sure it doesn't, always work in sub-folders and sometimes access to the root can be blocked. If you don't...

Openfiledialog1.showdialog() - exception 0x732e1175 (uxtheme.dll)

20 Jan 2020 by Paramu1973

Hi, I have a small project in VS2015, Windows Forms Applications accessing via shared folder using UNC paths for 4-systems. Windows Forms have OpenFileDialog() control. Actually it's working good in 3 systems. But 1 of the remaining user system showing exception 0x732E1175 (uxtheme.dll), at the...

I cant figure out my mistaked in C code

17 Jan 2020 by Member 14719581

Hello guys! whats up? I'm trying couple of hours to solve an annoying mistake and get the expected result but every try i do fails. Could you help me please? This is my source code: #define _CRT_SECURE_NO_WARNINGS #include #include #include #include ...

I cant figure out my mistaked in C code

17 Jan 2020 by Patrice T

Quote: I cant figure out my mistaked in C code You forgot to tell what is supposed to do your code ! We can't guess ! You forgot to tell us how the code go wrong (how you know it is wrong). The only sensible advice is to learn how to use the debugger. ----- Your code do not behave the way you...

I cant figure out my mistaked in C code

17 Jan 2020 by OriginalGriff

We have no idea what you expect that to do: even with the data, reporting it as "it don't work" doesn't help anybody - we can't see your screen, can't access your HDD, or read your mind. And we don't know what your tutor asked you to do! So, it's going to be up to you. Fortunately, you have a...

General error using PDO in PHP

28 Dec 2019 by Jassim Rahma

Hi, I am getting General Error but can't find the reason. The error I am getting is: PDOException: SQLSTATE[HY000]: General error in /home/domain.com/api/signin.php:40 Stack trace: #0 /home/domain.com/api/signin.php(40): PDOStatement->fetch() #1 {main}Connection failed: SQLSTATE[HY000]:...

Exception from HRESULT: 0x800A03EC Error

15 Oct 2019 by dashingly

I am getting "HRESULT: 0x800A03EC" error when running Excel add-in with following code: Excel.Range rng = ActiveSheet.Cells[x, y] as Excel.Range; string before = rng.Value2; string cleanV = System.Text.RegularExpressions.Regex.Replace(before, @"\s+", ""); ...

System IO exception on MOVEFILE - file in use by another process

16 Sep 2019 by Member 14557501

Okay... Once I walked away from the problem for a couple of days, and gave OriginalGriff's answer time to percolate in my subconscious, I found a solution. Looking at the code in my problem update, there is only one statement that opens a file, the "OpenFileDialog1.OpenFile()". I commented...

System IO exception on MOVEFILE - file in use by another process

16 Sep 2019 by Member 14557501

I am testing a new Visual Basic 2017 app which will let users select a file from a directory for processing. After processing the app is intended to move the file to a backup directory. This works for the first file just fine, but on the second file I get: System.IO.IOException: 'The process...

System IO exception on MOVEFILE - file in use by another process

13 Sep 2019 by OriginalGriff

Since your app is processing a file, it;'s highly likely that your app still has it open, and thus it's in use when the CopyFile call is made. Since it's opened for writing by something, it can't be opened for reading - the "open for write" operation establishes an exclusive lock on the file to...

Error while adding a web service reference in Silverlight application

24 Apr 2019 by Member 14328281

solamente evita usar nombres tan largos y cambia la direccion del proyecto a una ruta mas corta un ejemplo pasala al C y si tu proyecto se llama parangaricutirimicuariquense_mi_proyecto cambiale el nombre a ese proyecto a uno mas cortito y vuala

Hello, does anyone know how I can handle a system.formatexception

21 Apr 2019 by Happy_Accidents

I have no errors in my code, at least from what I can see on the error list. but every time I run my code it comes up with a system.formatexception. am new to coding and VB.NET so any advise on what I can do to solve this problem would help. What I have tried: Private Sub...

Hello, does anyone know how I can handle a system.formatexception

21 Apr 2019 by Gerry Schmitz

You wrote a method to format Currency; do the same for doubles. You can do the Double.TryParse in the routine and any default / error handling; returning a valid number. That way you limit the amount of code you need to write.

The serial port cannot be used immediately after being opened

6 Mar 2019 by cass3000

I have a problem with the serial port:My code:Dim readData() As ByteDim port As New SerialPort("COM1", 38400, Parity.None, 8)port.StopBits = StopBits.Oneport.Handshake = Handshake.Noneport.ReadTimeout = 1000port.Open()port.Read(readData, 0, 8)If readData.Length > 0...

How I Can Calling Com Object Multiple Time

10 Feb 2019 by Esraa Saady

i want to call function in matlab from c# inside for loop using com componentwhen i tried it i had this exceptionInvalid callee. (Exception from HRESULT: 0x80020010 (DISP_E_BADCALLEE))this is the codefor (int j = 1; j

How I Can Calling Com Object Multiple Time

10 Feb 2019 by Member 14145676

Hi, I'm sad to see all the unhelpful comments above when it is really Mathwork's poor implementation leading to this error. The solution is to simply include result = null in your for loop: for (int j = 1; j

C# WPF loading user stopping UNIQUE KEY constraint in SQL

1 Dec 2018 by TheBigBearNow

Hello all, I have a C# WPF application that I log into and I pass the user to the next screen. Then I click to go to a profile screen and if the user already has profile data I autopopulate all the fields. In my profile screen I have it so when you set the combobox to ‘Yes’ it creates the...

SelectedIndexChanged

C# WPF loading user stopping UNIQUE KEY constraint in SQL

1 Dec 2018 by #realJSOP

I know - it's unfortunate that you have to actually write some code, but that's how it goes. Put a try/catch block around the code that's attempting to insert the new user, and in the catch part, show a message box that shows "User name already exists.", and let that be that. At the same time.

SelectedIndexChanged

C# WPF skip messagebox in _selectionchanged()

30 Nov 2018 by TheBigBearNow

Hello all, I have a question with C# WPF I have a window that passes a User object into the next window and in the constructor I am setting a default combobox value to what the users property is. In the combobox_Selection() I have it so when this specific property is selected a...

SelectedIndexChanged

C# WPF skip messagebox in _selectionchanged()

30 Nov 2018 by Graeme_Grant

The code is doing exactly what you have asked it to do. When the selection changes, default is no selection, the SelectionChanged is fired from the ctor method. IF you set a breakpoint on the line CboCustomer.SelectedIndex = 2; then step through the execution line by line, you will see this...

SelectedIndexChanged

Ensuring an Error is Logged Only Once

28 Nov 2018 by Shai Cohen

By utilizing some fairly mundane features of .NET, we can log errors at the point where the exception occurred; preserving vital debug information while avoiding repetitive error logging.

I have a connection problem in C#

21 Nov 2018 by Member 14051204

I am in a university project group of six people, and we are using C# (with Microsoft Visual Studio 2017 as IDE) to make a program, that can manage a beer production system. I have a weird problem that i have no idea how to fix. Whenever I through Visual Studio, try to connect to a database or a...

I have a connection problem in C#

13 Nov 2018 by Aydin Homay

Hi, The information that you provided is not enough and to complicated. You are referring to several problems. Let`s make progress step-by-step. Follow my solution and leave comments I will read and change/improve the solution according to your progress until we get it solve. Ok? So first,...

Object reference not set to an instance of an object

11 Nov 2018 by Aydin Homay

Hi I am more suspicious to the below line: ComboboxState.SelectedValue.ToString() Could you please do a favor and re-write your code in this way: var userId = currentUser.UserID; var firstName = TextboxFirstName.Text; var lastName = TextboxLastName.Text; var address = TextboxAddress.Text;...

Object reference not set to an instance of an object

11 Nov 2018 by TheBigBearNow

Hello, I am getting the error object reference is not set to a instance I am creating a new customer in the combobox select method but in the button click I go to update the customer but I get an error where I am updating the customer object. The error is here in this btn click: this exact...

C# WPF object reference not set to an instance of an object

9 Nov 2018 by OriginalGriff

The debugger is pretty much the only way you will find this: if you aren't hitting the breakpoints, then either they aren't in the right place, or you are not debugging the code you are executing. So: try it again. Go to the "Debug" menu and select the "Exceptions..." menu item. In the...

C# WPF object reference not set to an instance of an object

9 Nov 2018 by TheBigBearNow

current error: Object reference not set to an instance of an object I was getting invalid cast exception error but i changed (int) to Convert.toInt32 and that went away. I go to debug it and the on my button click and the code runs all the way through not stopping at any of my breakpoints. The...

Getting "accessviolationexception" error after ms access 2016 installation

20 Sep 2018 by OriginalGriff

You get an "Access violation" error when the process trying to open a file does not have sufficient permissions for it. So start by looking at the file you are opening, the folder that contains it, and see exactly where it is, and what users have access rights. It's possible that Access 2016...

Getting "accessviolationexception" error after ms access 2016 installation

20 Sep 2018 by yash1507

Hi, Earlier ms access 2013 version was installed on machine. Now, ms access 2016 version has been installed. I didn't make any changes in code, but i am getting "a first chance exception of type 'system.accessviolationexception' occurred" error. I am using Microsoft Visual Studio...