Concatenating Strings Efficiently - The Diigo Meta page

• 27 Jul 14
  

  acazsouza

  .net c# performance string programming code

• 09 Feb 12
  

  meljeanlegaspi

  • Rules Of Thumb

     

      So, when should you use StringBuilder, and when should you use the string concatenation operators? 

     
     
    •   Definitely use StringBuilder when you're concatenating in a non-trivial loop - especially  if you don't know for sure (at compile time) how many iterations you'll make through the loop. For example,  reading a file a character at a time, building up a string as you go using the += operator is  potentially performance suicide. 
     
    •   Definitely use the concatenation operator when you can (readably) specify everything which needs to  be concatenated in one statement. (If you have an array of things to concatenate, consider calling  String.Concat explicitly - or String.Join if you need a delimiter.) 
     
    •   Don't be afraid to break literals up into several concatenated bits - the result will be the same.  You can aid readability by breaking a long literal into several lines, for instance, with no harm to  performance. 
     
    •   If you need the intermediate results of the concatenation for something other than feeding  the next iteration of concatenation, StringBuilder isn't going to help you. For instance, if  you build up a full name from a first name and a last name, and then add a third piece of information (the  nickname, maybe) to the end, you'll only benefit from using StringBuilder if you don't need  the (first name + last name) string for other purpose (as we do in the example which creates a Person  object). 
     
    •   If you just have a few concatenations to do, and you really want to do them in separate statements, it doesn't  really matter which way you go. Which way is more efficient will depend on the number of concatenations  the sizes of string involved, and what order they're concatenated in. If you really believe that piece  of code to be a performance bottleneck, profile or benchmark it both ways. 
     
• 26 May 10
  

  sanjayuttam

  "Concatenating Strings Efficiently"

  c# performance

• 04 Jan 10
  

  Pete Austin

  When not to use StringBuilder. Also see http://www.yoda.arachsys.com/csharp/strings.html

• 08 Sep 09
  

  Glenn Carr

  stringbuilder c#

• 15 Oct 08
  

  Martin Fierro

  StringBuilder when to use it

  String.Concat

• 29 Jul 08
  

  Craig Boal

  performance stringbuilder

• 25 Feb 08
  

  Olivier DUVAL

  bestpractices string object stringbuilder c#

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