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
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:
bool rich = true, famous = false;
A constant declaration is like a variable declaration, except that it cannot be changed after it has been declared, and the initialization must occur with the declaration (more on this in Constants):
constdouble c = 2.99792458E08;
The scope of a local variable or local constant variable extends throughout the current block. You cannot declare another local variable with the same name in the current block or in any nested blocks.
Expression statements are expressions that are also valid statements. In practice, this means expressions that “do” something; in other words, expressions that:
Assign or modify a variable
Instantiate an object
Call a method
Expressions that do none of these are not valid statements:
string s = "foo"; s.Length; // Illegal statement: does nothing!
When you call a constructor or a method that returns a value, you’re not obliged to use the result. However, unless the constructor or method changes state, the statement is useless:
new StringBuilder(); ...