Part 22  String & String Builder

we will discuss
1.  String
2.  String Builder

String 

String is a reference type and behaves like value type. String is sequence of characters or array of characters.A string is represented by class System.String. 

Example :

         string name = "Chandan"; //creating string using string keyword  
         String lname = "Pandey"; //creating string using String class  

string vs String

    1.The string keyword is an alias for String.String and string are equivalent

    2. String is a reference type and behaves like value type.

         string name = "Chandan"; //creating string using string keyword  
         String lname = "Pandey"; //creating string using String class  

  3. String are immutable the contents of a string object.string value can't be changed after the object is created and It can contain nulls.

               string name= "Chandan";

               string Lname= name;

               name+= "World";

               System.Console.WriteLine(Lname);

              //Output: chandan

  4. String, string and System.String means same and it will not affect the performance of the application.

            // "System.String" class

        System.String Name;




 5.The String is use to the System.String class methods, 

 6. String object is created, the value is stored within the dynamic memory, or on the Heap.

7. string can contains null value and if you declare the value '0' then compile time error.

8.  If any changes made to the string object like add or modify an existing value, then it will simply discard the old instance in memory and create a new instance to hold the new value.

String arrays: 

String array create the array of string.

 class Program

    {       

        static void Main(string[] args)

        {

            String[ ] s1 = new string[2];

            s1 [0] = "chandan";

            s1 [1] = "pandey";

            for (int i = 0; i < 2; i++)

            {

                Console.WriteLine("value at Index position " + i + " is " + s1 [i]);

            }

            Console.ReadKey();

        }

    }

Output

value at Index position 0 is chandan

value at Index position 1 is pandey

class Program

    {       

        static void Main(string[] args)

        {

            string s1 = "chandan";

            char[ ] ch = { 'c', 's', 'h', 'a', 'r', 'p' };

            string s2 = new string(ch);

            Console.WriteLine(s1);

            Console.WriteLine(s2);

            Console.ReadKey();

        }

    }

Output

chandan

csharp