 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
.NET Forum / Languages / C# / July 2007Some Interview questions
Why did u use stringbuilder instead of string for appending? I told him it is more efficient. He did not seem very convinced. So what should have been the exact answer. How many objects will be formed in the operation a=b+c; ? (a,b and c are objects) What is the difference between a pointer and reference ? a ptr can be null but a ref cannot be null... please elaborate .. i cant understand thru some code examples to clear my concept... Unemployed > Why did u use stringbuilder instead of string for appending? > > I told him it is more efficient. He did not seem very convinced. So > what should have been the exact answer. Could you say what your code actually was? Sometimes StringBuilder is more efficient - sometimes it isn't. See http://pobox.com/~skeet/csharp/stringbuilder.html for more information. > How many objects will be formed in the operation a=b+c; ? (a,b and c > are objects) It will depend on what the objects actually are. > What is the difference between a pointer and reference ? > > a ptr can be null but a ref cannot be null... please elaborate .. i > cant understand thru some code examples to clear my concept... A reference certainly can be null - in C#, at least. In C#, pointers are only used in unsafe code. Jon Suppose if the objects a,b and c are (three cases):- 1.int 2.float 3.belong to user-defined class like Date > Suppose if the objects a,b and c are (three cases):- > 1.int > 2.float > 3.belong to user-defined class like Date If they're all ints, no objects will be created. If they're all floats, no objects will be created. Not sure what you mean by Date - if you mean DateTime, it's a struct and you'd get a compile-time error because you can't add two DateTimes together. Jon > Why did u use stringbuilder instead of string for appending? > > I told him it is more efficient. He did not seem very convinced. So > what should have been the exact answer. If that is YOUR reason to use a StringBuilder then it is the correct answer in some respects. I use a StringBuilder if it makes the code cleaner and easier to understand what is happening. Performance (if improved) is an added benefit but it is not my primary reason to use it. > How many objects will be formed in the operation a=b+c; ? (a,b and c > are objects) [quoted text clipped - 3 lines] > a ptr can be null but a ref cannot be null... please elaborate .. i > cant understand thru some code examples to clear my concept... These last 2 questions seem pointless to me. I really don't know what they are trying to ascertain from asking questions like this. At least the first one finds out something of your rationale about your coding style. The first question I like to ask is "Have you read Design Patterns?" PS > Unemployed We always ask about design patterns too but it's amazing how many people can explain exactly what they are and give textbook responses of their impelmentation, but then 2 seconds later choose not to use them in an example where they obviously apply. Sam ------------------------------------------------------------ We're hiring! B-Line Medical is seeking .NET Developers for exciting positions in medical product development in MD/DC. Work with a variety of technologies in a relaxed team environment. See ads on Dice.com. >> Why did u use stringbuilder instead of string for appending? >> [quoted text clipped - 23 lines] > >> Unemployed Samuel R. Neff skrev: > We always ask about design patterns too but it's amazing how many > people can explain exactly what they are and give textbook responses > of their impelmentation, but then 2 seconds later choose not to use > them in an example where they obviously apply. Or use them where they are obviously overengineered solutions to problems that aren't there :)  SignatureHelge Free MagazinesGet these publications absolutely FREE for up to 12 months. There are no hidden fees and no obligation. Simply choose a title, complete the application form and submit it. Read more ...
|
Reply to this Message
|
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.