// Declare without initializing.
string message1;
// Initialize to null.
string message2 = null// Initialize as an empty string.
// Use the Empty constant instead of the literal "".
string message3 = System.String.Empty;
// Use System.String if you prefer.
System.String greeting = "Hello World!";
// Use a const string to prevent 'message4' from
// being used to store another string value.
const string message4 = "You can't get rid of me!";
// Use the String constructor only when creating
// a string from a char*, char[], or sbyte*.
// System.String documentation for details.
char[] letters = { 'A', 'B', 'C' };
string alphabet = new string(letters);