Swift
Using Replace Patterns in Email

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

Swift

func chilkatTest() {
    var success: Bool = 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.
    let emailTemplate = CkoEmail()!

    // 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.add(to: "FIRST_NAME", emailAddress: "RECIPIENT_EMAIL")

    emailTemplate.setHtmlBody(html: "<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(path: "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.

    let mailman = CkoMailMan()!

    emailTemplate.setReplacePattern(pattern: "FIRST_NAME", replace: "Elon")
    emailTemplate.setReplacePattern(pattern: "RECIPIENT_EMAIL", replace: "elon.musk@example.com")
    emailTemplate.setReplacePattern(pattern: "PRODUCT_NAME", replace: "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.
    var mime: String? = mailman.render(toMime: emailTemplate)
    print("\(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.
    var count: Int = emailTemplate.numReplacePatterns.intValue
    print("Number of replace patterns: \(count)")

    var i: Int = 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
        print("\(emailTemplate.getReplacePattern(index: i)!): \(emailTemplate.getReplaceString(index: i)!)")
        i = i + 1
    }

    // Or lookup a replacement pattern by name:
    var name: String? = "FIRST_NAME"
    print("\(name!) = \(emailTemplate.getReplaceString2(pattern: 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 = true
    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"
    // 		}	
    // 		...
    // 	]
    // }

    let json = CkoJsonObject()!
    success = json.loadFile(path: "qa_data/json/mail_merge.json")
    if success == false {
        print("\(json.lastErrorText!)")
        return
    }

    var emailAddr: String?
    var firstName: String?
    var product: String?

    i = 0
    count = json.size(ofArray: "mail_merge").intValue
    while i < count {
        json.i = i
        emailAddr = json.string(of: "mail_merge[i].to")
        firstName = json.string(of: "mail_merge[i].name")
        product = json.string(of: "mail_merge[i].product")

        emailTemplate.setReplacePattern(pattern: "FIRST_NAME", replace: firstName)
        emailTemplate.setReplacePattern(pattern: "RECIPIENT_EMAIL", replace: emailAddr)
        emailTemplate.setReplacePattern(pattern: "PRODUCT_NAME", replace: product)

        success = mailman.sendEmail(email: emailTemplate)
        if success == false {
            print("\(mailman.lastErrorText!)")
            return
        }

        print("Send email to \(emailAddr!)")

        i = i + 1
    }

    print("Success.")

}