Want to win a PS4? Go Premium and enter to win our High-Tech Treats giveaway. Enter to Win

x
?
Solved

if else or switch

Posted on 2011-03-18
6
Medium Priority
?
270 Views
Last Modified: 2012-05-11
Hi

This is a very common question that is similar to every programming.

My query is which language construct to use when and which is quicker.
0
Comment
Question by:KaranGupta
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
6 Comments
 
LVL 39

Accepted Solution

by:
Pratima Pharande earned 668 total points
ID: 35164443
switch statement is faster to execute than the if-else-if ladder. This is due to the compiler's ability to optimise the switch statement. In the case of the if-else-if ladder, the code must process each if statement in the order determined by the programmer. However, because each case within a switch statement does not rely on earlier cases, the compiler is able to re-order the testing in such a way as to provide the fastest execution.
0
 
LVL 39

Expert Comment

by:Pratima Pharande
ID: 35164448
when tou have one or two conditions go for if elese.
if you have ladderof if else if then go for switch
0
 
LVL 9

Assisted Solution

by:mayank_joshi
mayank_joshi earned 668 total points
ID: 35164461
As with most things you should pick which to use based on the context and what is conceptually the correct way to go. A switch is really saying "pick one of these based on this variables value" but an if statement is just a series of boolean checks.

As an example, if you were doing:

int value = // some value
if (value == 1) {
    doThis();
} else if (value == 2) {
    doThat();
} else {
    doTheOther();
}

This would be much better represented as a switch as it then makes it immediately obviously that the choice of action is occurring based on the value of "value" and not some arbitrary test.

Also, if you find yourself writing switches and if-elses and using an OO language you should be considering getting rid of them and using polymorphism to achieve the same result if possible.

Finally, regarding switch taking longer to type, I can't remember who said it but I did once read someone ask "is your typing speed really the thing that affects how quickly you code?" (paraphrased)
0
NFR key for Veeam Agent for Linux

Veeam is happy to provide a free NFR license for one year.  It allows for the non‑production use and valid for five workstations and two servers. Veeam Agent for Linux is a simple backup tool for your Linux installations, both on‑premises and in the public cloud.

 
LVL 6

Assisted Solution

by:openshac
openshac earned 664 total points
ID: 35164472
There are some performance tests at:

http://www.blackwasp.co.uk/SpeedTestIfElseSwitch.aspx

"The results show that the switch statement is faster to execute than the if-else-if ladder. This is due to the compiler's ability to optimise the switch statement. In the case of the if-else-if ladder, the code must process each if statement in the order determined by the programmer. However, because each case within a switch statement does not rely on earlier cases, the compiler is able to re-order the testing in such a way as to provide the fastest execution."
0
 
LVL 11

Expert Comment

by:SAMIR BHOGAYTA
ID: 35167891
Hello, If you want the application is quickly execute then my advice is you should use the switch() case .
0
 

Author Closing Comment

by:KaranGupta
ID: 35180028
Thanks
0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Creating an analog clock UserControl seems fairly straight forward.  It is, after all, essentially just a circle with several lines in it!  Two common approaches for rendering an analog clock typically involve either manually calculating points with…
Wouldn’t it be nice if you could test whether an element is contained in an array by using a Contains method just like the one available on List objects? Wouldn’t it be good if you could write code like this? (CODE) In .NET 3.5, this is possible…
In this video, Percona Solution Engineer Rick Golba discuss how (and why) you implement high availability in a database environment. To discuss how Percona Consulting can help with your design and architecture needs for your database and infrastr…
In response to a need for security and privacy, and to continue fostering an environment members can turn to for support, solutions, and education, Experts Exchange has created anonymous question capabilities. This new feature is available to our Pr…

636 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question