如何从mail（）中的电子邮件地址插入变量？

Question

How do I insert a variable form email address in the PHP mail() function?

$form_data =array();
$form_data['firstName'] = 'Joe';
$form_data['surname'] = 'Do';
$form_data['email'] = 'info@Domain';
print "From: ".$form_data['firstName']." ".$form_data['surname']." <".$form_data['email'].">\n";

When I wrap <> around then the email address is not displayed I have tried

print "<{$form_data['email']}>";
print '<'.$form_data['email'].'>';

But I don't know how to solve this

Complete code (using Wordpres wp_mail() function);

        //Send mail
$recipients[] = get_bloginfo('admin_email');
$email_subject = "Contactform - ". get_bloginfo('name');
$email_message = $tpl;      
$headers[] = "From: ".$form_data['firstName']." ".$form_data['surname']." <".$form_data['email'].">\n";       
$headers[] = "Content-Type: text/html\n";
$send =  wp_mail($recipients, $email_subject, $email_message, $headers);    

Answer 1

Try replacing the < and > with HTML escaped characters like so:

print "From: ".$form_data['firstName']." ".$form_data['surname']." <".$form_data['email'].">\n";

< = < and > = >

Answer 2

如果要显示它，请使用htmlspecialchars（） ：

print "From: ".$form_data['firstName']." ".$form_data['surname']." ".htmlspecialchars("<{$form_data['email']}>");