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GeneralRe: change data by using a removable disk Pin
Member 1504609315-Jan-21 5:45
Member 1504609315-Jan-21 5:45 
GeneralRe: change data by using a removable disk Pin
Dave Kreskowiak15-Jan-21 6:28
mveDave Kreskowiak15-Jan-21 6:28 
AnswerRe: change data by using a removable disk Pin
Ralf Meier15-Jan-21 9:05
mveRalf Meier15-Jan-21 9:05 
GeneralRe: change data by using a removable disk Pin
Richard Andrew x6418-Jan-21 11:55
professionalRichard Andrew x6418-Jan-21 11:55 
AnswerRe: change data by using a removable disk Pin
Richard MacCutchan14-Jan-21 8:55
mveRichard MacCutchan14-Jan-21 8:55 
AnswerRe: change data by using a removable disk Pin
Gerry Schmitz15-Jan-21 2:26
mveGerry Schmitz15-Jan-21 2:26 
QuestionNull reference exception occurs for no reason Pin
Alex Dunlop14-Jan-21 6:05
Alex Dunlop14-Jan-21 6:05 
AnswerRe: Null reference exception occurs for no reason Pin
OriginalGriff14-Jan-21 6:08
mveOriginalGriff14-Jan-21 6:08 
This is one of the most common problems we get asked, and it's also the one we are least equipped to answer, but you are most equipped to answer yourself.

Let me just explain what the error means: You have tried to use a variable, property, or a method return value but it contains null - which means that there is no instance of a class in the variable.
It's a bit like a pocket: you have a pocket in your shirt, which you use to hold a pen. If you reach into the pocket and find there isn't a pen there, you can't sign your name on a piece of paper - and you will get very funny looks if you try! The empty pocket is giving you a null value (no pen here!) so you can't do anything that you would normally do once you retrieved your pen. Why is it empty? That's the question - it may be that you forgot to pick up your pen when you left the house this morning, or possibly you left the pen in the pocket of yesterday's shirt when you took it off last night.

We can't tell, because we weren't there, and even more importantly, we can't even see your shirt, much less what is in the pocket!

Back to computers, and you have done the same thing, somehow - and we can't see your code, much less run it and find out what contains null when it shouldn't.
But you can - and Visual Studio will help you here. Run your program in the debugger and when it fails, VS will show you the line it found the problem on. You can then start looking at the various parts of it to see what value is null and start looking back through your code to find out why. So put a breakpoint at the beginning of the method containing the error line, and run your program from the start again. This time, VS will stop before the error, and let you examine what is going on by stepping through the code looking at your values.

But we can't do that - we don't have your code, we don't know how to use it if we did have it, we don't have your data. So try it - and see how much information you can find out!
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
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SuggestionRe: Null reference exception occurs for no reason Pin
Richard Deeming14-Jan-21 6:34
mveRichard Deeming14-Jan-21 6:34 
GeneralRe: Null reference exception occurs for no reason Pin
OriginalGriff14-Jan-21 6:49
mveOriginalGriff14-Jan-21 6:49 
AnswerRe: Null reference exception occurs for no reason Pin
Ralf Meier14-Jan-21 6:37
mveRalf Meier14-Jan-21 6:37 
GeneralRe: Null reference exception occurs for no reason Pin
Alex Dunlop14-Jan-21 6:49
Alex Dunlop14-Jan-21 6:49 
GeneralRe: Null reference exception occurs for no reason Pin
Ralf Meier14-Jan-21 6:51
mveRalf Meier14-Jan-21 6:51 
Questionlearning to code in c# Pin
grumpi_sc30010-Jan-21 20:30
grumpi_sc30010-Jan-21 20:30 
AnswerRe: learning to code in c# Pin
OriginalGriff10-Jan-21 21:01
mveOriginalGriff10-Jan-21 21:01 
AnswerRe: learning to code in c# Pin
Calin Negru10-Jan-21 21:39
Calin Negru10-Jan-21 21:39 
GeneralRe: learning to code in c# Pin
OriginalGriff10-Jan-21 23:11
mveOriginalGriff10-Jan-21 23:11 
GeneralRe: learning to code in c# Pin
Calin Negru11-Jan-21 0:21
Calin Negru11-Jan-21 0:21 
AnswerRe: learning to code in c# Pin
Gerry Schmitz11-Jan-21 5:00
mveGerry Schmitz11-Jan-21 5:00 
AnswerRe: learning to code in c# Pin
BryanFazekas21-Jan-21 5:33
BryanFazekas21-Jan-21 5:33 
QuestionBest release management for winform project Pin
Mou_kol8-Jan-21 5:03
Mou_kol8-Jan-21 5:03 
AnswerRe: Best release management for winform project Pin
Gerry Schmitz8-Jan-21 5:21
mveGerry Schmitz8-Jan-21 5:21 
GeneralRe: Best release management for winform project Pin
OriginalGriff8-Jan-21 8:45
mveOriginalGriff8-Jan-21 8:45 
GeneralRe: Best release management for winform project Pin
Mou_kol8-Jan-21 9:33
Mou_kol8-Jan-21 9:33 
GeneralRe: Best release management for winform project Pin
Mycroft Holmes8-Jan-21 11:37
professionalMycroft Holmes8-Jan-21 11:37 

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