Other Topics - Illustrated C# 2005 - page 531

Method Main
Every C# program must have one entry point—a method that must be called Main .
In the sample code throughout this text, I have used a version of Main that takes no param-
eters and returns no value. There are, however, four forms of Main that are acceptable as the
entry point to a program. These forms are the following:
￿ static void Main() {…}
￿ static void Main( string[] args) {…}
￿ static int Main() {…}
￿ static int Main( string[] args) {…}
The first two forms don't return a value to the execution environment when the program
terminates. The second two forms return an int value. A return value, if one is used, is generally
used to report success or failure of the program, where 0 is generally used to indicate success.
The second and fourth forms allow you to pass actual parameters, also called arguments ,
from the command line, into the program, when it starts. There can be zero or more of these
command-line arguments, separated by spaces or tabs. Each argument is interpreted by the pro-
gram as a string, but you do not need to enclose them in quotation marks on the command line.
For example, the following program called CommandLineArgs accepts command-line argu-
ments and prints out each argument supplied.
class Program
{
static void Main(string[] args)
{
foreach (string s in args)
Console.WriteLine(s);
}
}
The following command line executes program CommandLineArgs with five arguments.
CommandLineArgs Jon Peter Beth Julia Tammi
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Executable Arguments
name