(Delphi DLL) Send Email to Distribution List

Sends the same email to a list of 1000 email addresses in 50 sends where each email has 20 recipients.

Note: Chilkat is not intended nor designed for mass emailing. A solution such as this might be used for a corporate emailing to employees, or an emailing to newsletter subscribers.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, MailMan, BinData, StringTable, Email, StringBuilder;

...

procedure TForm1.Button1Click(Sender: TObject);
var
mailman: HCkMailMan;
success: Boolean;
email: HCkEmail;
bdMime: HCkBinData;
distList: HCkStringTable;
sbRecipients: HCkStringBuilder;
i: Integer;
szDistList: Integer;
j: Integer;

begin
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

mailman := CkMailMan_Create();

CkMailMan_putSmtpHost(mailman,'smtp.mymailserver.com');
CkMailMan_putSmtpPort(mailman,465);
CkMailMan_putSmtpSsl(mailman,True);
CkMailMan_putSmtpUsername(mailman,'myUsername');
CkMailMan_putSmtpPassword(mailman,'myPassword');

// Create a new email object
email := CkEmail_Create();
CkEmail_putSubject(email,'This is a test');
CkEmail_putBody(email,'This is a test');
CkEmail_putFrom(email,'Senders Name <sender@example.com>');
CkEmail_AddTo(email,'Subscribers','subscribers@example.com');

bdMime := CkBinData_Create();
CkMailMan_RenderToMimeBd(mailman,email,bdMime);

// Load a file containing one email address per line.
distList := CkStringTable_Create();
success := CkStringTable_AppendFromFile(distList,1000,'utf-8','qa_data/distList.txt');
if (success = False) then
  begin
    Memo1.Lines.Add(CkStringTable__lastErrorText(distList));
    Exit;
  end;

sbRecipients := CkStringBuilder_Create();

i := 0;
szDistList := CkStringTable_getCount(distList);
j := 0;
while i < szDistList do
  begin

    // Build a list of comma-separated recipients.
    if (j > 0) then
      begin
        CkStringBuilder_Append(sbRecipients,',');
      end;
    CkStringBuilder_Append(sbRecipients,CkStringTable__stringAt(distList,i));

    i := i + 1;
    j := j + 1;

    // If we have 20 recipients, or we have the final recipient in the final chunk, then send.
    if ((j = 20) or (i = szDistList)) then
      begin
        success := CkMailMan_SendMimeBd(mailman,'sender@example.com',CkStringBuilder__getAsString(sbRecipients),bdMime);
        if (success <> True) then
          begin
            Memo1.Lines.Add(CkMailMan__lastErrorText(mailman));
            Exit;
          end;
        j := 0;
        CkStringBuilder_Clear(sbRecipients);
      end;
  end;

success := CkMailMan_CloseSmtpConnection(mailman);
if (success <> True) then
  begin
    Memo1.Lines.Add('Connection to SMTP server not closed cleanly.');
  end;

Memo1.Lines.Add('Email sent to distirbution list.');

CkMailMan_Dispose(mailman);
CkEmail_Dispose(email);
CkBinData_Dispose(bdMime);
CkStringTable_Dispose(distList);
CkStringBuilder_Dispose(sbRecipients);

end;