如何在php中读取5美元符号($）后的字符字符串 - How to read the char string after 5 dollars sign ($) in php

How to read the char string after 5 dollars sign ($) in php

我想要一个php代码，它可以读取5个美元符号（$）后的字符字符串，实例输入：

ACCT_ID$ID_NUMBER$ID_TYPE$SMSC$FIRST_NAME$PROMO_CODE$MOBILE1$MOBILE2$OFFICE$HOUSE$

输出应该像：

PROMO_CODE$MOBILE1$MOBILE2$OFFICE$HOUSE$

这些代码可以工作，但没有regex

<?php
   $haystack = "ACCT_ID'$ID_NUMBER'$ID_TYPE'$SMSC'$FIRST_NAME'$PROMO_CODE'$MOBILE1'$MOBILE2'$OFFICE'$HOUSE'$";
   $needle = "$";
   $pos = -1;
   for ($i =0 ;$i < 5 ; $i++) {
     $pos = strpos($haystack, $needle, $pos+1);
   }
   $result = substr($haystack, $pos+1);
   $previous = substr($haystack, 0, $pos+1);
   $final = $previous."something to add".$result; //add something here.
   echo $result,PHP_EOL;
   echo $previous,PHP_EOL;
   echo $final,PHP_EOL;