In this article, I am explaining in detail What is the difference between a mutable and immutable string in C#. Please follow the below lines to understand this concept more precisely.

Immutable String

Immutable string can’t be alter, once we have assign a value to immutable object state can’t be changed. We can use System.String to use immutable string.

   String str = “Technology Crowds”;  //*  Immutable String Example
   string str = “Technology Crowds” + “Technology”;
Mutable vs Immutable

Mutable String

We can assign multiple values to mutable string and object state can be altered.
Best example of Mutable is stringbuilder object can be used. We can multiple concatenation to mutable string. Mutable have very good flexibility to change object state, mutable string can generate long string.
We can use given below namespace to use mutable string in c#

    using System.Text;   //*  namespace used to import string builder

  StringBuilder strLong = null;   //*  [Mutable String] example
  strLong.Append("Technology");
  strLong.Append("Crowds");

I have explained best practice about what is the difference between a mutable and immutable string in C#

Conclusion:

All string object are immutable in C#, String builder would allow us to work alternatively like as Mutable string in C#.

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