What is the difference between a mutable and immutable string in c

A mutable object can be changed after it's created, and an immutable object can't. In Java, everything except for strings is mutable by default:. There's no way to make existing objects immutable. Even if an object is declared final , its fields can still be changed:. That said, if you're defining your own class, you can make its objects immutable by making all fields final and private.

Strings can be mutable or immutable depending on the language. Any time you change a string e. If you want mutable strings in Java, you can use a StringBuilder object:. Or, you can convert the string to an array of characters, which will be mutable. Mutable objects are nice because you can make changes in-place , without allocating a new object.

But be careful—whenever you make an in-place change to an object, all references to that object will now reflect the change. Get the free 7-day email crash course. You'll learn how to think algorithmically , so you can break down tricky coding interview questions.

No prior computer science training necessary—we'll get you up to speed quickly, skipping all the overly academic stuff. Thank you for pointing that out PatriceSc. The content you requested has been removed. Ask a question. Quick access. Search related threads. Remove From My Forums.

Answered by:. Archived Forums. NET development 0 0. Sign in to vote. User posted Explain this concept with example. Wednesday, June 17, AM. 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. What is the difference between a mutable and immutable string in C?

Ask Question. Asked 10 years, 11 months ago. Active 9 months ago. Viewed k times. Improve this question. AMissico Venkadesh Venkadesh 1, 2 2 gold badges 12 12 silver badges 3 3 bronze badges.

It isn't identical. Very similar, but that's not the same as identical. Related question about the internals of StringBuilder stackoverflow. Add a comment. Active Oldest Votes. Net mutable string type To "effect a change" on a string represented as a C String , you actually create a new String object. If use a StringBuilder you only copy O N characters. And finally, for those people who assert that a StringBuilder is not a string because it is not immutable, the Microsoft documentation describes StringBuilder thus: "Represents a mutable string of characters.

This class cannot be inherited. Improve this answer. Stephen C Stephen C k 90 90 gold badges silver badges bronze badges. String is immutable i. But StringBuilder is not immutable rather, it is mutable so if you have to alter a string many times, such as multiple concatenations, then use StringBuilder.

Appulus Pankaj Agarwal Pankaj Agarwal What happens if you concat immutable strings many times? Loads of memory usage for strings without references? Or just slow? Rudie - both. Each concatenation creates a new String object, and copies all of the characters of both input strings. StephenC explained with the keywords.

That cleared my mind totally thanks Immutable String In C and. Substring 2 ; Console. WriteLine newString ; Console. WriteLine str ; This will print 'string' and 'mystring' respectively. Mutable String If you want to have a string which you want to modify often you can use the StringBuilder class. Salah Akbari Unmesh Kondolikar Unmesh Kondolikar 9, 3 3 gold badges 33 33 silver badges 50 50 bronze badges. Beautiful explanation! Adam Norberg Adam Norberg 3, 15 15 silver badges 21 21 bronze badges.

Immutable : When you do some operation on a object, it creates a new object hence state is not modifiable as in case of string. Mutable When you perform some operation on a object, object itself modified no new obect created as in case of StringBuilder. Stephen C k 90 90 gold badges silver badges bronze badges.

TalentTuner TalentTuner StringBuilder is mutable equivalent of System. Append "initial value" ; sb. AppendLine "second value" ; sb. StringBuilder [mscorlib]System. It has almost nothing to do with mutable versus immutable. It escapes me why some people think that disassembling some irrelevant example code is going to help people understand this kind of thing. For a start, most programmers are not fluent in CLI code. Strings are mutable because. NET use string pool behind the scene.

I hope it will help. Rahul Garg Rahul Garg 3, 29 29 silver badges 30 30 bronze badges. None, actually. The String class is mutable. Copy "I am immutable. James Ko James Ko