http://community.csdn.net/Expert/TopicView3.asp?id=5320418
Returns a specified parameter from the command-line.
返回当前命令行的详细参数信息
Unit
System
Category
command line utilities
Delphi syntax:
function ParamStr(Index: Integer): string;
C++ syntax:
extern PACKAGE AnsiString __fastcall ParamStr(int Index);
Description
ParamStr returns the parameter from the command line that corresponds to Index, or an empty string if Index is greater than ParamCount. For example, an Index value of 2 returns the second command-line parameter.
On Windows, ParamStr(0) returns the path and file name of the executing program (for example, C:\TEST\MYPROG.EXE).
On Linux, ParamStr(0) returns the command used to execute the program, without parameters (for example, ./myprogram). This behavior is dependent on information returned by the shell program and may not be consistent among all shells.
Note: Use double quotes to wrap multiple words as one parameter (such as long file names containing spaces).
ParamStr(0) 在windows下返回应用程序路径和文件名称（含扩展名），参数则从1开始，
“function ParamCount: Integer;
”则返回存在的参数数量
另：
Delphi syntax:
var CmdLine: PChar platform;
下次再学。。。