用 GetEnvironmentVariable 获取常用系统变量 -var

　s: string

begin

　s := GetCurrentDir

　ShowMessage(s)　{C:\Documents and Settings\wy\My Documents\RAD Studio\Projects}



　SetCurrentDir( .. )

　s := GetCurrentDir

　ShowMessage(s)　{C:\Documents and Settings\wy\My Documents\RAD Studio}



　SetCurrentDir( ..\.. )

　s := GetCurrentDir

　ShowMessage(s)　{C:\Documents and Settings\wy}

end