Name and emp? Age evaluated to valid values. In case of emp. City , emp? State , emp? Country and emp? For example, In below case, Age property is a value type and emp?. Age returns int? So while assigning it to a variable then you have to declare the variable as nullable type.
In below case we have declared int? For example, when we invoke emp?. If emp is NULL then no further call in the expression will occur.
If you club null conditional operator?. However it will throw a Null Reference Exception if the left operand of? For example: emp?. However emp. Thanks for your time feel free to provide your feedback and do check my other blogs on Null Coalescing Operator?? This is important for team environments with source code.
It is not a contest to write code with the fewest characters. It is a contest to write code with can be modified with the least disruption.
This site uses Akismet to reduce spam. Learn how your comment data is processed. Imagine that something goes wrong deep in something that doOtherStuff calls. All you get back is an Exception object, thrown at the throw in AddData. No stack trace, no call information, no state, nothing at all to indicate the real source of the problem, unless you go in and switch your debugger to break on exception thrown rather than exception unhandled. If you are catching an exception and just re-throwing it in any way , particularly if the code in the try block is in any way nontrivial, do yourself and your colleagues, present and future a favor and throw out the entire try - catch block.
Granted, throw; is better than the alternatives, but you are still giving yourself or whoever else is trying to fix a bug in the code completely unnecessary headaches. This is not to say that try-catch-throw is necessarily evil per se, as long as you do something relevant with the exception object that was thrown inside the catch block.
Then there's the potential problems of catching Exception in the first place, but that's another matter, particularly since in this particular case you throw an exception. Another thing that strikes me as more than a little dangerous is that data could potentially change value during the execution of the function, since you are passing by reference. So the null check might pass but before the code gets to doing anything with the value, it's changed - perhaps to null.
I'm not positive if this is a concern or not it might not be , but it seems worth watching out for. Whenever you are creating objects of class you have to check the whether the object is null or not using the below code. Wait for final versions or use your own environment to test, before assuming true beta software without any sort of documentation or demonstration from your end.
I just followed a method that we would usually follow in java script. To convert object to string and then check whether they are null.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Checking if an object is null in C Ask Question. Asked 10 years, 6 months ago.
Active 3 months ago. Viewed 1. I would like to prevent further processing on an object if it is null. In the following code I check if the object is null by either: if! Equals null and if data!
Improve this question. Peter Mortensen You should also use throw e; versus throw new Exception e. ToString ; — Nix. Equals will always throw an exception if the object is null. Nix: throw e; is not much better. ToString will produce a string that includes not only the error message, but also those of all InnerExceptions and the stack trace. So that's kind of a very fat-heavy exception message. If you rightly! Usually you catch exceptions to gracefully handle them, clean up resources better with "finally" clause or do some sort of logging before re-throwing the exception.
Show 5 more comments. Active Oldest Votes. It's not data that is null , but dataList. Aside The correct way to check for nullity is if data! Improve this answer. Jon Jon k 74 74 gold badges silver badges bronze badges. I've seen also Object. ReferenceEquals obj, null for this purpose. Is it to avoid equality overrides? LucaPiccioni I've used it to prevent value-type-complains when using generics: geekality. I prefer null! Just to extend your answer: whenever you see a NullReferenceException , you'll generally see that the null object is followed by a.
Using that as a rule of thumb, it becomes clear that the exception for datalist. Add data can only be about datalist. Comparatively; for datalist. Value , the problem could be either in datalist or data.
Footnote: I had not seen that this was a 7 year necropost. I'm sorry — Flater. Show 1 more comment. I wonder is there an "isn't null"?
Wish they'd implement if obj aint null : — Nick Bull. For isn't null there is if obj is object — yatskovsky. OrnKristjansson because! I miss the IsNot operator from VB. If C had allowed such an implicit conversion to boolean, you are much more likely to run into programming errors like this:.
Normally C prevents such mistakes so although Dmitry's answer is clever, I'd advise against it. If you want to Throw an ArgumentNullException e. If the variable is null, the exception is thrown. In Visual Studio you can add a custom snippet to bind this line to the shortcut arg0.
You only need to type arg0 , double press the TAB key, and to type the parameter name. Implementing a null check then only takes 2 seconds. Here is the snippet. You can use object class static method ReferenceEquals method to find out if the refrence is null or not.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Shortest null check in c Ask Question. Asked 7 years, 2 months ago. Active 1 year, 9 months ago. Viewed 2k times. Is there a shorter way to write this in c : if myobject! I found some similar questions, but they're asking slightly different things: C Shortest Way to Check for Null and Assign Another Value if Not Best and fastest way to check if an object is null How to determine if variable is 'undefined' or 'null'?
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