Functions comprise statements that execute sequentially in the textual order in which they appear. A statement block is a series of statements appearing between braces (the {} tokens).

Declaration Statements

A declaration statement declares a new variable, optionally initializing the variable with an expression. A declaration statement ends in a semicolon. You may declare multiple variables of the same type in a comma-separated list. For example:

	string someWord = "rosebud";
	int someNumber = 42;
	bool rich = true, famous = false;

A constant declaration is like a variable declaration, except that the variable cannot be changed after it has been declared, and the initialization must occur with the declaration:

	const double c = 2.99792458E08;
	c+=10; // error

Local variables

The scope of a local or constant variable extends to the end of the current block. You cannot declare another local variable with the same name in the current block or in any nested blocks. For example:

	static void Main()
	  int x;
	    int y;
	    int x;               // Error, x already defined
	    int y;               // OK, y not in scope
	  Console.WriteLine(y);  // Error, y is out of scope

Expression Statements

Expression statements are expressions that are also valid statements. An expression statement must either change state or call something that might change state. Changing state essentially means changing a variable. The possible expression statements are:

  • Assignment expressions (including increment and decrement expressions)

  • Method call ...

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