StringBuilder Class In C#

Strings are one of most frequent use data types in C#. Strings in C# are immutable means that once a string is created, it cannot be changed. No characters can be added or removed from it, nor can its length be changed.

The String object is immutable while StringBuilder object is mutable. Both String and StringBuilder are reference type. But String acts like a value type.

StringBuilder is located in the System.Text namespace.

The System.Text.StringBuilder class can be used when you want to modify a string without creating a new object. Using the StringBuilder class can boost performance when concatenating many strings together in a loop.

The following table lists the methods you can use to modify the contents of a StringBuilder.

Method	Description
StringBuilder.Append	Appends information to the end of the current StringBuilder.
StringBuilder.AppendFormat	Replaces a format specifier passed in a string with formatted text.
StringBuilder.Insert	Inserts a string or object into the specified index of the current StringBuilder.
StringBuilder.Remove	Removes a specified number of characters from the current StringBuilder.
StringBuilder.Replace	Replaces a specified character at a specified index.