C#

using System.Collections.Generic ;

...

Dictionary<string,object> mystuff   = new Dictionary<string,object>() ;
Dictionary<string,object> yourstuff = new Dictionary<string,object>() ;
Dictionary<string,object> hisstuff  = new Dictionary<string,object>() ;

using LookupTable=System.Collections.Generic.Dictionary<string,object> ;

...

LookupTable mystuff   = new LookupTable() ;
LookupTable yourstuff = new LookupTable() ;
LookupTable hisstuff  = new LookupTable() ;

using DatabaseConnection=System.Data.SqlClient.SqlConnection  ;
using DatabaseCommand   =System.Data.SqlClient.SqlCommand     ;
using DatabaseReader    =System.Data.SqlClient.SqlDataReader  ;
using DatabaseParameter =System.Data.SqlClient.SqlParameter   ;
using DatabaseAdapter   =System.Data.SqlClient.SqlDataAdapter ;
...

# if SqlClient
    using DatabaseConnection=System.Data.SqlClient.SqlConnection  ;
    using DatabaseCommand   =System.Data.SqlClient.SqlCommand     ;
    using DatabaseReader    =System.Data.SqlClient.SqlDataReader  ;
    using DatabaseParameter =System.Data.SqlClient.SqlParameter   ;
    using DatabaseAdapter   =System.Data.SqlClient.SqlDataAdapter ;
    ...
# endif

# if OleDb
    ...
# endif

# if MySql
    ...
# endif

...

# define SqlClient   1
# define OleDb       2
# define MySql       3
# define UseDatabase 1

# if (UseDatabase==SqlClient)
    using DatabaseConnection=System.Data.SqlClient.SqlConnection  ;
    using DatabaseCommand   =System.Data.SqlClient.SqlCommand     ;
    using DatabaseReader    =System.Data.SqlClient.SqlDataReader  ;
    using DatabaseParameter =System.Data.SqlClient.SqlParameter   ;
    using DatabaseAdapter   =System.Data.SqlClient.SqlDataAdapter ;
    ...
# endif

# if (UseDatabase==OleDb)
   ...
# endif

# if (UseDatabase==MySql)
   ...
# endif

using WinForms=System.Windows.Forms ;
using WebForms=System.Web.UI.WebControls ;

...

WinForms.Button b1 = new WinForms.Button() ;
WebForms.Button b2 = new WebForms.Button() ;

Vodstok wrote:

at the top of a .cs file

The "From:" field specifies the author(s) of the message,
that is, the mailbox(es) of the person(s) or system(s) responsible
for the writing of the message. The "Sender:" field specifies the
mailbox of the agent responsible for the actual transmission of the
message. For example, if a secretary were to send a message for
another person, the mailbox of the secretary would appear in the
"Sender:" field and the mailbox of the actual author would appear in
the "From:" field. If the originator of the message can be indicated
by a single mailbox and the author and transmitter are identical, the
"Sender:" field SHOULD NOT be used. Otherwise, both fields SHOULD
appear.

The originator fields also provide the information required when
replying to a message. When the "Reply-To:" field is present, it
indicates the mailbox(es) to which the author of the message suggests
that replies be sent. In the absence of the "Reply-To:" field,
replies SHOULD by default be sent to the mailbox(es) specified in the
"From:" field unless otherwise specified by the person composing the
reply.

In all cases, the "From:" field SHOULD NOT contain any mailbox that
does not belong to the author(s) of the message.

If there is a delivery failure after acceptance of a message, the
receiver-SMTP MUST formulate and mail a notification message. This
notification MUST be sent using a null ("<>") reverse path in the
envelope. The recipient of this notification MUST be the address
from the envelope return path (or the Return-Path: line).

logicaldna wrote:

What is the diff between Sender property of MailMessage and From property of MailMessage.
What is the difference between ReplyTO and ReturnPath
they have same meaning in usage. dont they ?
Now my client wants to use these things with unique cases

Scott Dorman wrote:

if a secretary were to send a message for
another person, the mailbox of the secretary would appear in the
"Sender:" field and the mailbox of the actual author would appear in
the "From:" field.

Scott Dorman wrote:

It sounds like you are trying to write an SMTP compliant email system

namespace cvsreadapp
{
    class CVSreader
    {
        public static bool ReadFile(string sFileName, out string[][] saJaggedArray)
        {
            bool bReturnValue = false;
            try
            {
                string[] sFile;
                int i=0;
                StreamReader srFileIO = null;
                FileStream fsFileIO = null;
                // open output file
                fsFileIO = new FileStream(sFileName, FileMode.Open, FileAccess.Read);
                srFileIO = new StreamReader(fsFileIO);
                // read file
                sFile = srFileIO.ReadToEnd().Split('\n');
                saJaggedArray = new string[sFile.Length][];
                foreach (string x in sFile)
                {
                    saJaggedArray[i] = new string[3];
                    saJaggedArray[i] = x.Split(',');
                }
                srFileIO.Close();
                fsFileIO.Close();
                bReturnValue = true;
            }
            catch
            {
                bReturnValue = false;
            }
            return bReturnValue;
        }
    }
    class MyApp
    {
        static void main(string[] args)
        {
            string[][] jaggedarray;
            if (!CVSreader.ReadFile("mycvsfile.cvs", out jaggedarray))
            {
                Console.WriteLine("Error reading CVS file");
            }
            foreach (string[] i in jaggedarray)
            {
                foreach (string j in i)
                {
                    Console.Write(string.Concat(i," "));
                }
                Console.Write('\n');
            }
        }
    }
}