WordPress函数：sanitize_email 给 email 地址“消消毒”

函数原型：

sanitize_email( string $email ): string

删除电子邮件中不允许使用的所有字符。

参数说明：

$email 要处理的邮件地址

返回值：

处理后的邮件地址

函数源码：

function sanitize_email( $email ) {
	// Test for the minimum length the email can be.
	if ( strlen( $email ) < 6 ) {
		return apply_filters( 'sanitize_email', '', $email, 'email_too_short' );
	}

	// Test for an @ character after the first position.
	if ( strpos( $email, '@', 1 ) === false ) {
		return apply_filters( 'sanitize_email', '', $email, 'email_no_at' );
	}

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

	$local = preg_replace( '/[^a-zA-Z0-9!#$%&\'*+\/=?^_`{|}~\.-]/', '', $local );
	if ( '' === $local ) {
		return apply_filters( 'sanitize_email', '', $email, 'local_invalid_chars' );
	}

	$domain = preg_replace( '/\.{2,}/', '', $domain );
	if ( '' === $domain ) {
		return apply_filters( 'sanitize_email', '', $email, 'domain_period_sequence' );
	}

	// Test for leading and trailing periods and whitespace.
	$domain = trim( $domain, " \t\n\r\0\x0B." );
	if ( '' === $domain ) {
		return apply_filters( 'sanitize_email', '', $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 ) ) {
		return apply_filters( 'sanitize_email', '', $email, 'domain_no_periods' );
	}

	// Create an array that will contain valid subs.
	$new_subs = array();

	// Loop through each sub.
	foreach ( $subs as $sub ) {
		// Test for leading and trailing hyphens.
		$sub = trim( $sub, " \t\n\r\0\x0B-" );

		// Test for invalid characters.
		$sub = preg_replace( '/[^a-z0-9-]+/i', '', $sub );

		// If there's anything left, add it to the valid subs.
		if ( '' !== $sub ) {
			$new_subs[] = $sub;
		}
	}

	// If there aren't 2 or more valid subs.
	if ( 2 > count( $new_subs ) ) {
		return apply_filters( 'sanitize_email', '', $email, 'domain_no_valid_subs' );
	}

	// Join valid subs into the new domain.
	$domain = implode( '.', $new_subs );

	// Put the email back together.
	$sanitized_email = $local . '@' . $domain;

	// Congratulations, your email made it!
	return apply_filters( 'sanitize_email', $sanitized_email, $email, null );
}

包含钩子：

apply_filters( ‘sanitize_email’, string $sanitized_email, string $email, string|null $message )

使用举例：

$sanitized_email = sanitize_email('    admin@example.com!');
echo $sanitized_email; // will output: 'admin@example.com'