C# 0 The Complete Reference

string

 data type. Thus, 

string

 is a reference type. Moreover, 

string

 is C#’s name for 

System.String

, the standard .NET string type. Thus, a C# string has 

access to all of the methods, properties, fields, and operators defined by 

String

.

Once a string has been created, the character sequence that comprises a string cannot be 

altered. This restriction allows C# to implement strings more efficiently. Though this restriction 

probably sounds like a serious drawback, it isn’t. When you need a string that is a variation 

on one that already exists, simply create a new string that contains the desired changes, 

and discard the original string if it is no longer needed. Because unused string objects are 

automatically garbage-collected, you don’t need to worry about what happens to the discarded 

strings. It must be made clear, however, that 

string

 reference variables may, of course, change 

the object to which they refer. It is just that the character sequence of a specific 

string

 object 

cannot be changed after it is created.

To create a string that can be changed, C# offers a class called