Delphi ActiveX
Using Replace Patterns in Email

Demonstrates how to use the replace patterns (mail-merge) feature in Chilkat MailMan.
Chilkat Delphi ActiveX Downloads

Delphi ActiveX
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
emailTemplate: TChilkatEmail;
mailman: TChilkatMailMan;
mime: WideString;
count: Integer;
i: Integer;
name: WideString;
json: TChilkatJsonObject;
emailAddr: WideString;
firstName: WideString;
product: WideString;

begin
success := 0;

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

// ---------------------------------------------------------------------
// Create an email template for sending.
emailTemplate := TChilkatEmail.Create(Self);

// We're going to replace "FIRST_NAME" with an actual name.
// We arbitrarily chose "FIRST_NAME".  We can choose anything, such as "CUSTOMER_NAME" or "THE_RECIPIENT_NAME"...
emailTemplate.Subject := 'Hello FIRST_NAME,';

emailTemplate.From := 'john@example.com';
emailTemplate.AddTo('FIRST_NAME','RECIPIENT_EMAIL');

emailTemplate.SetHtmlBody('<html><body><h2>Hello FIRST_NAME,</h2><p>Your order for PRODUCT_NAME has been shipped.</p></body></html>');

// If the email is saved to a file, we can see what it contains:
emailTemplate.SaveEml('qa_output/emailTemplate.eml');

// For example:

// MIME-Version: 1.0
// Date: Tue, 26 Apr 2022 07:10:52 -0500
// Message-ID: <715CF231A9F07B0B9FDB073518CD94138D791866@XYZ>
// Content-Type: text/html; charset=us-ascii
// Content-Transfer-Encoding: 7bit
// X-Priority: 3 (Normal)
// Subject: Hello FIRST_NAME,
// From: john@example.com
// To: FIRST_NAME <RECIPIENT_EMAIL>
// 
// <html><body><h2>Hello FIRST_NAME,</h2><p>Your order for PRODUCT_NAME has been shipped.</p></body></html>

// ---------------------------------------------------------------------
// Demonstrate replace patterns by setting and then rendering to MIME.

mailman := TChilkatMailMan.Create(Self);

emailTemplate.SetReplacePattern('FIRST_NAME','Elon');
emailTemplate.SetReplacePattern('RECIPIENT_EMAIL','elon.musk@example.com');
emailTemplate.SetReplacePattern('PRODUCT_NAME','Twitter Corporation');

// Render to MIME to see what we get.
// Note: When the MailMan sends an email, it renders the email to MIME and then sends.
// The rendering process is to do replacements, or possibly sign, encrypt, etc.
// When MailMan.SendEmail is called, internally the email is rendered, and the rendered email is sent.
// The equivalent to MailMan.Send email is to call email.RenderToMime followed by MailMan.SendMime.
mime := mailman.RenderToMime(emailTemplate.ControlInterface);
Memo1.Lines.Add(mime);

// This is the rendered MIME:

// MIME-Version: 1.0
// Date: Tue, 26 Apr 2022 07:25:49 -0500
// Message-ID: <750582BCDC891C67B48CEE2293C08B902C3891E9@XYZ>
// Content-Type: text/html; charset=us-ascii
// Content-Transfer-Encoding: 7bit
// X-Priority: 3 (Normal)
// Subject: Hello Elon,
// From: john@example.com
// To: Elon <elon.musk@example.com>
// 
// <html><body><h2>Hello Elon,</h2><p>Your order for Twitter Corporation has been shipped.</p></body></html>

// Note: When rendering, the Date and Message-ID headers are automatically regenerated.

// ---------------------------------------------------------------------
// An application can see what replacement patterns it previously set by calling SetReplacePattern multiple times.
count := emailTemplate.NumReplacePatterns;
Memo1.Lines.Add('Number of replace patterns: ' + IntToStr(count));

i := 0;
while i < count do
  begin
    // Note: The GetReplaceString method was found to not be working correctly.  It was returning the same value as GetReplacePattern.
    // It is fixed in Chilkat v9.5.0.91
    Memo1.Lines.Add(emailTemplate.GetReplacePattern(i) + ': ' + emailTemplate.GetReplaceString(i));
    i := i + 1;
  end;

// Or lookup a replacement pattern by name:
name := 'FIRST_NAME';
Memo1.Lines.Add(name + ' = ' + emailTemplate.GetReplaceString2(name));

// Sample output:

// Number of replace patterns: 3
// FIRST_NAME: Elon
// RECIPIENT_EMAIL: elon.musk@example.com
// PRODUCT_NAME: Twitter Corporation
// FIRST_NAME = Elon

// ---------------------------------------------------------------------
// Finally... demonstrate sending emails using the replacement patterns.
// 

// Set our mail server settings..
mailman.SmtpHost := 'smtp.mail.us-west-2.awsapps.com';
mailman.SmtpSsl := 1;
mailman.SmtpPort := 465;

mailman.SmtpUsername := 'john@example.com';
mailman.SmtpPassword := 'the_password';

// Imagine we have data in JSON format, and we wish to send the templated email to each recipient...
// 

// {
// 	"mail_merge" : [
// 		{
// 			"to": "mary@example.com",
// 			"name": "Mary",
// 			"product": "Widget 1" 
// 		},
// 		{
// 			"to": "robert@example.com",
// 			"name": "Robert",
// 			"product": "Widget 2"
// 		}	
// 		...
// 	]
// }

json := TChilkatJsonObject.Create(Self);
success := json.LoadFile('qa_data/json/mail_merge.json');
if (success = 0) then
  begin
    Memo1.Lines.Add(json.LastErrorText);
    Exit;
  end;

i := 0;
count := json.SizeOfArray('mail_merge');
while i < count do
  begin
    json.I := i;
    emailAddr := json.StringOf('mail_merge[i].to');
    firstName := json.StringOf('mail_merge[i].name');
    product := json.StringOf('mail_merge[i].product');

    emailTemplate.SetReplacePattern('FIRST_NAME',firstName);
    emailTemplate.SetReplacePattern('RECIPIENT_EMAIL',emailAddr);
    emailTemplate.SetReplacePattern('PRODUCT_NAME',product);

    success := mailman.SendEmail(emailTemplate.ControlInterface);
    if (success = 0) then
      begin
        Memo1.Lines.Add(mailman.LastErrorText);
        Exit;
      end;

    Memo1.Lines.Add('Send email to ' + emailAddr);

    i := i + 1;
  end;

Memo1.Lines.Add('Success.');
end;