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C

Using Replace Patterns in Email

See more Email Object Examples

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

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C
#include <C_CkEmail.h>
#include <C_CkMailMan.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEmail emailTemplate;
    HCkMailMan mailman;
    const char *mime;
    int count;
    int i;
    const char *name;
    HCkJsonObject json;
    const char *emailAddr;
    const char *firstName;
    const char *product;

    success = FALSE;

    //  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 = CkEmail_Create();

    //  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"...
    CkEmail_putSubject(emailTemplate,"Hello FIRST_NAME,");

    CkEmail_putFrom(emailTemplate,"john@example.com");
    CkEmail_AddTo(emailTemplate,"FIRST_NAME","RECIPIENT_EMAIL");

    CkEmail_SetHtmlBody(emailTemplate,"<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:
    CkEmail_SaveEml(emailTemplate,"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 = CkMailMan_Create();

    CkEmail_SetReplacePattern(emailTemplate,"FIRST_NAME","Elon");
    CkEmail_SetReplacePattern(emailTemplate,"RECIPIENT_EMAIL","elon.musk@example.com");
    CkEmail_SetReplacePattern(emailTemplate,"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 = CkMailMan_renderToMime(mailman,emailTemplate);
    printf("%s\n",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 = CkEmail_getNumReplacePatterns(emailTemplate);
    printf("Number of replace patterns: %d\n",count);

    i = 0;
    while (i < count) {
        //  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
        printf("%s: %s\n",CkEmail_getReplacePattern(emailTemplate,i),CkEmail_getReplaceString(emailTemplate,i));
        i = i + 1;
    }

    //  Or lookup a replacement pattern by name:
    name = "FIRST_NAME";
    printf("%s = %s\n",name,CkEmail_getReplaceString2(emailTemplate,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..
    CkMailMan_putSmtpHost(mailman,"smtp.mail.us-west-2.awsapps.com");
    CkMailMan_putSmtpSsl(mailman,TRUE);
    CkMailMan_putSmtpPort(mailman,465);

    CkMailMan_putSmtpUsername(mailman,"john@example.com");
    CkMailMan_putSmtpPassword(mailman,"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 = CkJsonObject_Create();
    success = CkJsonObject_LoadFile(json,"qa_data/json/mail_merge.json");
    if (success == FALSE) {
        printf("%s\n",CkJsonObject_lastErrorText(json));
        CkEmail_Dispose(emailTemplate);
        CkMailMan_Dispose(mailman);
        CkJsonObject_Dispose(json);
        return;
    }

    i = 0;
    count = CkJsonObject_SizeOfArray(json,"mail_merge");
    while (i < count) {
        CkJsonObject_putI(json,i);
        emailAddr = CkJsonObject_stringOf(json,"mail_merge[i].to");
        firstName = CkJsonObject_stringOf(json,"mail_merge[i].name");
        product = CkJsonObject_stringOf(json,"mail_merge[i].product");

        CkEmail_SetReplacePattern(emailTemplate,"FIRST_NAME",firstName);
        CkEmail_SetReplacePattern(emailTemplate,"RECIPIENT_EMAIL",emailAddr);
        CkEmail_SetReplacePattern(emailTemplate,"PRODUCT_NAME",product);

        success = CkMailMan_SendEmail(mailman,emailTemplate);
        if (success == FALSE) {
            printf("%s\n",CkMailMan_lastErrorText(mailman));
            CkEmail_Dispose(emailTemplate);
            CkMailMan_Dispose(mailman);
            CkJsonObject_Dispose(json);
            return;
        }

        printf("Send email to %s\n",emailAddr);

        i = i + 1;
    }

    printf("Success.\n");


    CkEmail_Dispose(emailTemplate);
    CkMailMan_Dispose(mailman);
    CkJsonObject_Dispose(json);

    }