c# - How can i send email one after one in a row? -

in form1 in backgroundworkerdowork event did:

se.sendphotos(photofilesdir + "\\" + "photofiles.zip"); se.sendphotos(photofilesdir1 + "\\" + "photofiles.zip"); se.sendphotos(photofilesdir2 + "\\" + "photofiles.zip"); se.sendphotos(photofilesdir3 + "\\" + "photofiles.zip"); 

in se class sendemail did:

public void sendphotos(string filenametosend)         {             try             {                 mailaddress = new mailaddress("test@gmail.com", "user " + (char)0xd8 + " name",                 system.text.encoding.utf8);                 mailaddress = new mailaddress("test@test");                 photosmessage = new mailmessage(from, to);                 photosmessage.body = "please check log file attachment have bugs.";                 string somearrows = new string(new char[] { '\u2190', '\u2191', '\u2192', '\u2193' });                 photosmessage.body += environment.newline + somearrows;                 photosmessage.bodyencoding = system.text.encoding.utf8;                 photosmessage.subject = "log file checking bugs" + somearrows;                 photosmessage.subjectencoding = system.text.encoding.utf8;                 attachment myattachment = new attachment(filenametosend, mediatypenames.application.octet);                 photosmessage.attachments.add(myattachment);                 smtpclient photossend = new smtpclient("smtp.gmail.com", 587);                 photossend.sendcompleted += new sendcompletedeventhandler(photossend_sendcompleted);                 photossend.enablessl = true;                 photossend.timeout = 10000;                 photossend.deliverymethod = smtpdeliverymethod.network;                 photossend.usedefaultcredentials = false;                 photossend.credentials = new networkcredential("usern", "userpass");                 string userstate = "test message1";                 photossend.sendasync(photosmessage, userstate);                 sendlogfile.enabled = false;                 fname = filenametosend;             }              catch (exception errors)             {                 logger.write("error sending message :" + errors);             }         }          private void photossend_sendcompleted(object sender, asynccompletedeventargs e)         {             photosmessage.dispose();             if (fname == @"c:\users\simbalip\appdata\local\outputphotos\photosfiles3" + "\\" + "photofiles.zip")             {                 photossendended = true;             }         } 

the problem in backgroundworkerdowork never send last 1 photofilesdir3. used breakpoint , getting : photossendended = true; in email im getting 3 files sent me , not 4.

when used breakpoint on backgroundworker , did f11 saw doing 4 sendings 1 after 1 without waiting .

each time photofiles.zip have different files inside. check did breakpoint on line:

if (fname == @"c:\users\simbalip\appdata\local\outputphotos\photosfiles3" + "\\" + "photofiles.zip") 

and when there time true == fname never c:\users\simbalip\appdata\local\outputphotos\photosfiles2 or 1 or photosfiles

but in end im getting 3 different photofiles.zip files each contain different files 1 of files never sent.

myabe need make somehow when send email somehow untill first 1 sent send next 1 in process there waitforexit() maybe emails ?

the documentation smtpclient alludes fact doesn't support parallel operations.

if there e-mail transmission in progress , call sendasync or send again, receive invalidoperationexception.

http://msdn.microsoft.com/en-us/library/system.net.mail.smtpclient.aspx

i recommend not sending next email until sendcompleted event has been raised. means drastic change in code (where each call sendphotos adds collection of pending send mail operations process in background)