repo_zf1/documentation/manual/en/module_specs/Zend_Validate-EmailAddress.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- Reviewed: no -->
<sect2 id="zend.validate.set.email_address">
    <title>EmailAddress</title>

    <para>
        <classname>Zend_Validate_EmailAddress</classname> allows you to validate an email address.
        The validator first splits the email address on local-part @ hostname and attempts to match
        these against known specifications for email addresses and hostnames.
    </para>

    <sect3 id="zend.validate.set.email_address.basic">
        <title>Basic usage</title>

        <para>
            A basic example of usage is below:
        </para>

        <programlisting language="php"><![CDATA[
$validator = new Zend_Validate_EmailAddress();
if ($validator->isValid($email)) {
    // email appears to be valid
} else {
    // email is invalid; print the reasons
    foreach ($validator->getMessages() as $message) {
        echo "$message\n";
    }
}
]]></programlisting>

        <para>
            This will match the email address <varname>$email</varname> and on failure populate
            <code>$validator->getMessages()</code> with useful error messages.
        </para>
    </sect3>

    <sect3 id="zend.validate.set.email_address.complexlocal">
        <title>Complex local parts</title>

        <para>
            <classname>Zend_Validate_EmailAddress</classname> will match any valid email address
            according to RFC2822. For example, valid emails include <code>bob@domain.com</code>,
            <code>bob+jones@domain.us</code>, <code>"bob@jones"@domain.com</code> and
            <code>"bob jones"@domain.com</code>
        </para>

        <para>
            Some obsolete email formats will not currently validate (e.g. carriage returns or a
            "\" character in an email address).
        </para>
    </sect3>

    <sect3 id="zend.validate.set.email_address.hostnametype">
        <title>Validating different types of hostnames</title>

        <para>
            The hostname part of an email address is validated against <link
                linkend="zend.validate.set.hostname">
                <classname>Zend_Validate_Hostname</classname></link>. By default
            only DNS hostnames of the form <code>domain.com</code> are accepted, though if you wish
            you can accept IP addresses and Local hostnames too.
        </para>

        <para>
            To do this you need to instantiate <classname>Zend_Validate_EmailAddress</classname>
            passing a parameter to indicate the type of hostnames you want to accept. More details
            are included in <classname>Zend_Validate_Hostname</classname>, though an example of how
            to accept both DNS and Local hostnames appears below:
        </para>

        <programlisting language="php"><![CDATA[
$validator = new Zend_Validate_EmailAddress(
                    Zend_Validate_Hostname::ALLOW_DNS |
                    Zend_Validate_Hostname::ALLOW_LOCAL);
if ($validator->isValid($email)) {
    // email appears to be valid
} else {
    // email is invalid; print the reasons
    foreach ($validator->getMessages() as $message) {
        echo "$message\n";
    }
}
]]></programlisting>
    </sect3>

    <sect3 id="zend.validate.set.email_address.checkacceptance">
        <title>Checking if the hostname actually accepts email</title>

        <para>
            Just because an email address is in the correct format, it doesn't necessarily mean
            that email address actually exists. To help solve this problem, you can use MX
            validation to check whether an MX (email) entry exists in the DNS record for the
            email's hostname. This tells you that the hostname accepts email, but doesn't tell you
            the exact email address itself is valid.
        </para>

        <para>
            MX checking is not enabled by default and at this time is only supported by UNIX
            platforms. To enable MX checking you can pass a second parameter to the
            <classname>Zend_Validate_EmailAddress</classname> constructor.
        </para>

        <programlisting language="php"><![CDATA[
$validator = new Zend_Validate_EmailAddress(Zend_Validate_Hostname::ALLOW_DNS,
                                            true);
]]></programlisting>

        <para>
            Alternatively you can either pass <constant>TRUE</constant> or
            <constant>FALSE</constant> to <code>$validator->setValidateMx()</code> to enable or
            disable MX validation.
        </para>

        <para>
            By enabling this setting network functions will be used to check for the presence of an
            MX record on the hostname of the email address you wish to validate. Please be aware
            this will likely slow your script down.
        </para>
    </sect3>

    <sect3 id="zend.validate.set.email_address.validateidn">
        <title>Validating International Domains Names</title>

        <para>
            <classname>Zend_Validate_EmailAddress</classname> will also match international
            characters that exist in some domains. This is known as International Domain Name (IDN)
            support. This is enabled by default, though you can disable this by changing the
            setting via the internal <classname>Zend_Validate_Hostname</classname> object that
            exists within <classname>Zend_Validate_EmailAddress</classname>.
        </para>

        <programlisting language="php"><![CDATA[
$validator->hostnameValidator->setValidateIdn(false);
]]></programlisting>

        <para>
            More information on the usage of <methodname>setValidateIdn()</methodname> appears in
            the <classname>Zend_Validate_Hostname</classname> documentation.
        </para>

        <para>
            Please note IDNs are only validated if you allow DNS hostnames to be validated.
        </para>
    </sect3>

    <sect3 id="zend.validate.set.email_address.validatetld">
        <title>Validating Top Level Domains</title>

        <para>
            By default a hostname will be checked against a list of known TLDs. This is enabled by
            default, though you can disable this by changing the setting via the internal
            <classname>Zend_Validate_Hostname</classname> object that exists within
            <classname>Zend_Validate_EmailAddress</classname>.
        </para>

        <programlisting language="php"><![CDATA[
$validator->hostnameValidator->setValidateTld(false);
]]></programlisting>

        <para>
            More information on the usage of <methodname>setValidateTld()</methodname> appears in
            the <classname>Zend_Validate_Hostname</classname> documentation.
        </para>

        <para>
            Please note TLDs are only validated if you allow DNS hostnames to be validated.
        </para>
    </sect3>

    <sect3 id="zend.validate.set.email_address.setmessage">
        <title>Setting messages</title>

        <para>
            <classname>Zend_Validate_EmailAddress</classname> makes also use of
            <classname>Zend_Validate_Hostname</classname> to check the hostname part of a given
            email address. As with Zend Framework 1.10 you can simply set messages for
            <classname>Zend_Validate_Hostname</classname> from within
            <classname>Zend_Validate_EmailAddress</classname>.
        </para>

        <programlisting language="php"><![CDATA[
$validator = new Zend_Validate_EmailAddress();
$validator->setMessages(array(Zend_Validate_Hostname::UNKNOWN_TLD => 'I don't know the TLD you gave'));
]]></programlisting>

        <para>
            Before Zend Framework 1.10 you had to attach the messages to your own
            <classname>Zend_Validate_Hostname</classname>, and then set this validator within
            <classname>Zend_Validate_EmailAddress</classname> to get your own messages returned.
        </para>
    </sect3>
</sect2>
<!--
vim:se ts=4 sw=4 et:
-->