How can I send an email to different addresses?

CFv6 version

Supposing your dropdown field or radio button is named "user_email", go under "Events" > "Logic" and drag a "Switch" action to the "submit" event, make sure the new switch action is BEFORE (above) the "Email" action.

In the "Data provider" field of the "Switch" action write: {data:user_email}

In the "Values setup" enter multiple lines, each of them in this format: dropdown_value:email_address

em1:first@domain.com
em2:second@domain.com
em3:third@domain.com

Now set the "Switch" action "Name" to "email_address" for example, in your "Email" action "Recipients" just write {var:email_address} to capture the result of the switch action which is an email address.

CFV5 version

em1=This address
em2=That address
em3=The other address

<?php
// set a default recipient
$recipient = 'em1';
if ( isset($form->data['recipients']) && $form->data['recipients'] ) {
  $recipient = $form->data['recipients'];
}
$emails = array (
  'em1' => 'bob@example.com',
  'em2' => 'info@example.net',
  'em3' => 'admin@example.com' );
$form->data['email_to_use'] = $emails[$recipient];
?>

OR if you want the user to be able to select more than one address. In this case my form has a select dropdown or checkbox group named recipients[].

// set a default recipient
$recipients = array( 'em1' );
if ( !empty( $form->data['recipients'] ) ) {
  $recipients = $form->data['recipients'];
}
$emails = array (
  'em1' => 'bob@example.com',
  'em2' => 'info@example.net',
  'em3' => 'admin@example.com' 
);
$emails_to_use = array();
foreach ( $recipients as $v ) {
  $emails_to_use[] = $emails[$v];
}
$emails_to_use = implode(',',  $emails_to_use);
$form->data['emails_to_use'] = $emails_to_use;
?>

<?php
// set a default recipient
$recipients = array( 'em1' );
if ( isset($form->data['recipients']) && $form->data['recipients'] ) {
  $recipients = $form->data['recipients'];
}
$emails = array (
  'em1' => array('bob@example.com', 'john@example.com'),
  'em2' => array('info@example.net'),
  'em3' => array('admin@example.com', 'admin@example.org') 
);
$emails_to_use = array();
foreach ( $recipients as $v ) {
  $emails_to_use = array_merge($emails[$v], $emails_to_use);
}
$emails_to_use = implode(',',  $emails_to_use);
$form->data['emails_to_use'] = $emails_to_use;
?>

<?php
if ( !empty($form->data['email2']) ) {
  $mailto = array($form->data['email1'], $form->data['email2']);
  $mailto = implode(',', $mailto);
} else {
  $mailto = $form->data['email1'];
}
$form->data['email_to_use'] = $mailto;
?>

c) Also in the OnSubmit event after the Custom Code action I have an Email action with the Dynamic To box on the Advanced tab set to email_to_use or emails_to_use The email action is enabled and has standard Static values for Subject, From Name and From Email.

CFV4 version

em1=This address
em2=That address
em3=The other address 

<?php
$recipient = JRequest::getString('recipients', 'em1', 'post');
$emails = array (
  'em1' => 'bob@example.com',
  'em2' => 'info@example.net',
  'em3' => 'admin@example.com' );
$form->data['email_to_use'] = $emails[$recipient];
?>

For ChronoForms v3 and earlier

First include the following in your Form HTML:

. . .
Select the recipient you wish to contact:
<select name="recipients">
  <option value="em1">Name 1
  <option value="em2">Name 2
  <option value="em3">Name 3
  . . . 
</select>
. . . 

Then enter this code in the 'On Submit code - before sending email' field:

For ChronoForms 3.1 and 3.2

<?php
$emails_2 = array( 
  'em1'=>'sample1@email.com', 
  'em2'=>'sample2@email.com', 
  'em3'=>'name_3@example.com', 
  . . . 
); 
$MyForm =& CFChronoForm::getInstance('form_name_here'); 
$MyFormEmails =& CFEMails::getInstance($MyForm->formrow->id); 
$MyFormEmails->setEmailData(1, 'to', $emails_2[$_POST['recipients']]); 
?>

<?php
$emails_2 = array('em1'=>'sample1@email.com', 'em2'=>'sample2@email.com', 'em3'=>'name_3@example.com', . . .);
$emails[0]->to .= ','.$emails_2[$_POST['recipients']];
?>

<?php
$emails = array(
  'em1'=>'name_1@example.com', 
  'em2'=>'name_2@example.com', 
  'em3'=>'name_3@example.com', 
  . . .
);
$rows[0]->extraemail = $emails[$_POST['recipients']];
?>