Question

is_email( string $email,  bool $deprecated = false )

Verifies that an email is valid.

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description

Does not grok i18n domains. Not RFC compliant.

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参数

$email

(string) (Required) Email address to verify.

$deprecated

(bool) (Optional) Deprecated.

Default value: false

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返回值

(string|bool) Either false or the valid email address.

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源代码

File: wp-includes/formatting.php

function is_email( $email, $deprecated = false ) {
	if ( ! empty( $deprecated ) )
		_deprecated_argument( __FUNCTION__, '3.0.0' );

	// Test for the minimum length the email can be
	if ( strlen( $email ) < 6 ) {
		/**
		 * Filters whether an email address is valid.
		 *
		 * This filter is evaluated under several different contexts, such as 'email_too_short',
		 * 'email_no_at', 'local_invalid_chars', 'domain_period_sequence', 'domain_period_limits',
		 * 'domain_no_periods', 'sub_hyphen_limits', 'sub_invalid_chars', or no specific context.
		 *
		 * @since 2.8.0
		 *
		 * @param bool   $is_email Whether the email address has passed the is_email() checks. Default false.
		 * @param string $email    The email address being checked.
		 * @param string $context  Context under which the email was tested.
		 */
		return apply_filters( 'is_email', false, $email, 'email_too_short' );
	}

	// Test for an @ character after the first position
	if ( strpos( $email, '@', 1 ) === false ) {
		/** This filter is documented in wp-includes/formatting.php */
		return apply_filters( 'is_email', false, $email, 'email_no_at' );
	}

	// Split out the local and domain parts
	list( $local, $domain ) = explode( '@', $email, 2 );

	// LOCAL PART
	// Test for invalid characters
	if ( !preg_match( '/^[a-zA-Z0-9!#$%&\'*+\/=?^_`{|}~\.-]+$/', $local ) ) {
		/** This filter is documented in wp-includes/formatting.php */
		return apply_filters( 'is_email', false, $email, 'local_invalid_chars' );
	}

	// DOMAIN PART
	// Test for sequences of periods
	if ( preg_match( '/\.{2,}/', $domain ) ) {
		/** This filter is documented in wp-includes/formatting.php */
		return apply_filters( 'is_email', false, $email, 'domain_period_sequence' );
	}

	// Test for leading and trailing periods and whitespace
	if ( trim( $domain, " \t\n\r\0\x0B." ) !== $domain ) {
		/** This filter is documented in wp-includes/formatting.php */
		return apply_filters( 'is_email', false, $email, 'domain_period_limits' );
	}

	// Split the domain into subs
	$subs = explode( '.', $domain );

	// Assume the domain will have at least two subs
	if ( 2 > count( $subs ) ) {
		/** This filter is documented in wp-includes/formatting.php */
		return apply_filters( 'is_email', false, $email, 'domain_no_periods' );
	}

	// Loop through each sub
	foreach ( $subs as $sub ) {
		// Test for leading and trailing hyphens and whitespace
		if ( trim( $sub, " \t\n\r\0\x0B-" ) !== $sub ) {
			/** This filter is documented in wp-includes/formatting.php */
			return apply_filters( 'is_email', false, $email, 'sub_hyphen_limits' );
		}

		// Test for invalid characters
		if ( !preg_match('/^[a-z0-9-]+$/i', $sub ) ) {
			/** This filter is documented in wp-includes/formatting.php */
			return apply_filters( 'is_email', false, $email, 'sub_invalid_chars' );
		}
	}

	// Congratulations your email made it!
	/** This filter is documented in wp-includes/formatting.php */
	return apply_filters( 'is_email', $email, $email, null );
}

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更新日志

Version	description
0.71	Introduced.

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相关函数

Uses

• wp-includes/formatting.php: is_email
• wp-includes/functions.php: _deprecated_argument()
• wp-includes/plugin.php: apply_filters()

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Used By

• wp-includes/rest-api.php: rest_validate_value_from_schema()
• wp-includes/user.php: wp_authenticate_email_password()
• wp-includes/comment.php: wp_handle_comment_submission()
• wp-admin/includes/ms.php: update_option_new_admin_email()
• wp-admin/includes/ms.php: send_confirmation_on_profile_email()
• wp-admin/includes/schema.php: populate_network()
• wp-admin/includes/user.php: edit_user()
• wp-includes/formatting.php: sanitize_option()
• wp-includes/user.php: register_new_user()
• wp-includes/ms-functions.php: newblog_notify_siteadmin()
• wp-includes/ms-functions.php: newuser_notify_siteadmin()
• wp-includes/ms-functions.php: wpmu_validate_user_signup()
• wp-includes/ms-deprecated.php: validate_email()
• wp-includes/ms-deprecated.php: get_user_id_from_string()
• wp-includes/class-wp-xmlrpc-server.php: wp_xmlrpc_server::wp_newComment()
Show 10 more used by Hide more used by

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User Contributed Notes

1. Skip to note content You must log in to vote on the helpfulness of this noteVote results for this note: 1You must log in to vote on the helpfulness of this note Contributed by Codex

   Example

   
   if ( is_email( 'email@domain.com' ) ) {
   	echo 'email address is valid.';
   }