如何从 preg_match 切换到 preg_replace？

Question

请看下面的代码：

来自：http://www.damnsemicolon.com/php/php-parse-email-body-email-piping

//get rid of any quoted text in the email body
$body_array = explode("\n",$body);
$message = "";
foreach($body_array as $key => $value){

    //remove hotmail sig
    if($value == "_________________________________________________________________"){
        break;

    //original message quote
    } elseif(preg_match("/^-*(.*)Original Message(.*)-*/i",$value,$matches)){
        break;

    //check for date wrote string
    } elseif(preg_match("/^On(.*)wrote:(.*)/i",$value,$matches)) {
        break;

    //check for From Name email section
    } elseif(preg_match("/^On(.*)$fromName(.*)/i",$value,$matches)) {
        break;

    //check for To Name email section
    } elseif(preg_match("/^On(.*)$toName(.*)/i",$value,$matches)) {
        break;

    //check for To Email email section
    } elseif(preg_match("/^(.*)$toEmail(.*)wrote:(.*)/i",$value,$matches)) {
        break;

    //check for From Email email section
    } elseif(preg_match("/^(.*)$fromEmail(.*)wrote:(.*)/i",$value,$matches)) {
        break;

    //check for quoted ">" section
    } elseif(preg_match("/^>(.*)/i",$value,$matches)){
        break;

    //check for date wrote string with dashes
    } elseif(preg_match("/^---(.*)On(.*)wrote:(.*)/i",$value,$matches)){
        break;

    //add line to body
    } else {
        $message .= "$value\n";
    }

}

//compare before and after
echo "$body<br><br><br>$message";

$body 包含完整的电子邮件正文，如果这是回复，则包括引用区域，此循环删除引用区域以获取新的回复作为 $message。但正如那里所建议的那样，循环速度很慢，最好使用 preg_replace 代替。那我该怎么办？

用什么替换模式？我也应该删除 foreach 循环吗？我在下面创建了没有 foreach 循环但似乎错了？请指教。

$patterns = array(
"_________________________________________________________________",
"/^-*(.*)Original Message(.*)-*/i",
"/^On(.*)wrote:(.*)/i",
"/^On(.*)$fromName(.*)/i",
"/^On(.*)$toName(.*)/i",
"/^(.*)$toEmail(.*)wrote:(.*)/i",
"/^(.*)$fromEmail(.*)wrote:(.*)/i",
"/^>(.*)/i",
"/^---(.*)On(.*)wrote:(.*)/i");

$message = preg_replace($patterns, '', $body);

Answer 1

您已经将范围缩小到一个可行的解决方案。只有几件事需要解决：

1. 正如@mario 评论的那样，您需要为^s 设置/m 修饰符以匹配每行的开头。
2. 您的第一个模式需要用分隔符括起来，并锚定到 ^ 和行尾，以保持与原始代码中相同的含义。
3. 包含换行符以删除整行。
4. 确保设置了变量$fromName、$fromEmail等。
5. 找到匹配项后，使用(?s:.*) 匹配从那里到正文末尾的所有内容。

代码：

$patterns = array(
    "/^_{30,}$(?s:.*)/m",
    "/^.*Original Message(?s:.*)/im",
    "/^(?:---.*)?On .* wrote:(?s:.*)/im",
    "/^On .* $fromName(?s:.*)/im",
    "/^On .* $toName(?s:.*)/im",
    "/^.*$toEmail(.*)wrote:(?s:.*)/im",
    "/^.*$fromEmail.* wrote:(?s:.*)/im",
    "/^>.*/ims",
);
$message = preg_replace($patterns, '', $body);
echo "$body<br><br><br>$message";

Run this code here

---

忠告：

考虑到它也会像这样剥离行：

only thing I wrote: ...