我有这个功能，可以为我发送各种电子邮件：

function tps_send_email($emailTo, $subject, $content) {
    //Allow HTML in email
    function tps_set_html_email_content_type() {
        return \'text/html\';
    }
    add_filter( \'wp_mail_content_type\', \'tps_set_html_email_content_type\' );

    //Send the email
    $mailSent = wp_mail($emailTo, $subject, $content);

    //Reset HTML content type back to text only (avoids conflicts)
    remove_filter( \'wp_mail_content_type\', \'tps_set_html_email_content_type\' );

    return $mailSent;
}

我使用它，这样我就不必在每次发送wp\\U邮件时手动设置内容类型。但是，如果我在另一个函数中多次使用此函数，就像这样：

function my_custom_function(){
    $mailTo = \'[email protected]\';
    $subject = \'Some subject line\';

    $emailTemplate1 = \'template 1 content goes here\';
    tps_send_email($emailTo, $subject, $emailTemplate1 );

    if (some condition) {
        $emailTemplate2 = \'template 2 content goes here\';
        //send another email
        tps_send_email($emailTo, $subject, $emailTemplate2  );
    }
}

第一封邮件发送正常，但第二封邮件会抛出错误Fatal error: Cannot redeclare tps_set_html_email_content_type()... （这是我的tps_send_email() 函数）。

我做错了什么？

function tps_set_html_email_content_type() {
    return \'text/html\';
}

function tps_send_email($emailTo, $subject, $content) {
    add_filter( \'wp_mail_content_type\', \'tps_set_html_email_content_type\' );

    //Send the email
    $mailSent = wp_mail($emailTo, $subject, $content);

    //Reset HTML content type back to text only (avoids conflicts)
    remove_filter( \'wp_mail_content_type\', \'tps_set_html_email_content_type\' );

    return $mailSent;
}