PHP 7.0 STRPOS未按预期运行

所以我想用 STRPO 为了测试变量中是否存在字符串,但在我所有使if语句工作的尝试中,都没有成功,所以我开始输出字符串,并试图找到 STRPO 发现了它,但它不是,尽管它很明显在那里!在这种情况下,我将在SMTP错误输出中搜索Gmail SMTP错误代码。
我知道如何修复错误,但我希望我的系统能够解析smtp错误并将其报告给我的用户。。。

PHP代码:

$Request = RequestPasswordReset($_POST["email"]);
echo $Request;
echo "<br>Position of Error Code: " . strpos($Request, "gsmtp SMTP code: 550");
die();
if($Request === "SUCCESS") {
    DisplayError("Password Reset Successful", "We have sent a email that contains a link to reset your password.", "/account/resetpassword.php");
} else if($Request === "USER_NOT_FOUND") {
    DisplayError("Password Reset Request Failed", "The specified email is not tied to any accounts in our system.", "/account/resetpassword.php");
} else if(strpos($Request, "gsmtp SMTP code: 550") !== false) {
    DisplayError("Password Reset Request Failed", "The mail was blocked by our relay due to IPs being not whitelisted.", "/account/resetpassword.php");
} else {
    DisplayError("Password Reset Request Failed", "The request failed for an unknown reason.", "/account/resetpassword.php");
}

文本输出:
它确实在重复,我重复了 $Request 两次,它确实做了下面两次

以下发件人地址失败:XXXXXXX:MAIL-From命令失败,中继[XXXXXXX]的凭据无效。您在G套件SMTP中继服务中注册的IP地址与发送此电子邮件的帐户的域不匹配。如果您试图中继来自未在G Suite帐户下注册或具有空信封的域的邮件,则必须将邮件服务器配置为使用SMTP身份验证来标识发送域,或在HELO或EHLO命令中显示您的域名之一。有关更多信息,请访问 https://support.google.com/a/answer/6140680#invalidcred r126sm1314271qke。4-gsmtp,550,5.7.1SMTP服务器错误:MAIL FROM命令失败详细信息:中继[XXXXXXX]的凭据无效。您在G套件SMTP中继服务中注册的IP地址与发送此电子邮件的帐户的域不匹配。如果您试图中继来自未在G Suite帐户下注册或具有空信封的域的邮件,则必须将邮件服务器配置为使用SMTP身份验证来标识发送域,或在HELO或EHLO命令中显示您的域名之一。有关更多信息,请访问 https://support.google.com/a/answer/6140680#invalidcred r126sm1314271qke。4-gsmtp SMTP代码:550其他SMTP信息:5.7.1
错误代码位置:

(编辑)重置密码请求功能:

function RequestPasswordReset($Email) {
// Try to Get User
$User = GetUser_Email($Email);

// Does user exist?
if($User === "NOT_FOUND") {
  return "USER_NOT_FOUND";
}

// Generate Link To Send with Email
$Link = GeneratePasswordResetLink();
$SendEmail = SendPasswordReset($User["Email"], $User["FirstName"] . $User["LastName"], $Link);

if($SendEmail !== "SUCCESS") {
  return $SendEmail;
} else {
  // WHAT IF MYSQL FAILS????? ~~~~~~~~~~~~~~~ NEED  SOLOUTION
  $PDO_Connection = CreateMySQLConnection();
  $PDO_CMD = $PDO_Connection -> prepare("UPDATE accounts SET ResetPassword=? WHERE Email=?");
    $PDO_CMD -> execute(array($Link, $User["Email"]));
  return "SUCCESS";
}
}

(编辑)发送密码重置功能:

$User = GetUser_ResetID($resetID);

$mail = CreateSMTPConnection();
$mail->AddAddress($targetAddress, $targetName);       // Add a recipient

$mail->IsHTML(true);                                  // Set email format to HTML
$mail->Subject = 'LitenUp Password Reset';
$mail->Body    = str_replace("https://mylitenup.net/account/resetpassword.php?ID=", ("https://mylitenup.net/account/resetpassword.php?ID=" . $resetID), file_get_contents($_SERVER['DOCUMENT_ROOT'] . "/php/mailer/documents/resetpassword.html"));
$mail->AltBody = 'Reset Your Password: https://mylitenup.net/account/resetpassword.php?ID=' . $resetID;
$mail->XMailer = 'LitenUp Mailer';
$mail->XPriority = '1';

  try{
    $mail->send();
    return "SUCCESS";
  } catch (phpmailerException $e) {
    return $e->errorMessage();
  } catch (\Exception $e) {
    return $e->getMessage();
  }

(编辑):我试过了 mb_strpos ,但它不起作用,所以如果这是有效的,为什么它对我不起作用?我做的 mb_strpos($Request, "gsmtp SMTP code: 550"); ,但在执行后,它会回显请求,但 Position of Error Code: 线路没有回声。

(更新1):我真的很抱歉耽搁了,最坏的情况下,我会再次悬赏。然而,你们是对的!当我第一次遇到错误时,我将其输出并复制了行“gsmtp SMTP代码:550”,但在完成标记后,似乎出现了某种新的行。您可以在 该行应该更像“gsmtp”++“SMTP代码:550”,但我不确定应该是什么换行符。我试过了
和\n。