Ruby

Enumerate the Header Fields of an Email

Demonstrates the read-only Chilkat Email.NumHeaderFields property together with GetHeaderFieldName and GetHeaderFieldValue to enumerate every header field. Indexing is zero-based, so fields run from 0 to NumHeaderFields - 1. Repeated header fields (a field name that appears more than once) are counted separately. This example builds a small email and prints each header field.

Background: A header field is a single Name: value line at the top of a MIME message. The same field name can legitimately appear multiple times — for example, a message can carry several Received lines, one added by each mail server it passed through. That is why enumerating by index (rather than looking up by name) matters: it lets you see every occurrence in the order it appears.

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Ruby

require 'chilkat'

#  Demonstrates the read-only Email.NumHeaderFields property and enumerating each
#  header field by zero-based index using GetHeaderFieldName and GetHeaderFieldValue.

email = Chilkat::CkEmail.new()
email.put_Subject("Header field enumeration")
email.put_From("mary@example.com")
email.AddTo("Joe","joe@example.com")

n = email.get_NumHeaderFields()
print "NumHeaderFields = " + n.to_s() + "\n";

for i in 0 .. n - 1
    print email.getHeaderFieldName(i) + ": " + email.getHeaderFieldValue(i) + "\n";
end