php - 如何使用Php从具有特定开始和结束位置的字符串中提取数据？

Question

我有一个代码，它有助于根据选定的值从文本文件中检索行。我希望它只返回从位置 166 开始到 177 结束的字符串的特定部分，而不是整行。我怎样才能做到这一点，有人可以帮助我。
代码:

<?php
$file = 'masterfile.out';
$searchfor = '125302532569';

// the following line prevents the browser from parsing this as HTML.
header('Content-Type: text/plain');

// get the file contents, assuming the file to be readable (and exist)
$contents = file_get_contents($file);
// escape special characters in the query
$pattern = preg_quote($searchfor, '/');
// finalise the regular expression, matching the whole line
$pattern = "/^.*$pattern.*\$/m";

// search, and store all matching occurrences in $matches
if(preg_match_all($pattern, $contents, $matches)){
   echo "Found matches:\n";
   echo implode("\n", $matches[0]);

}
else{
   echo "No matches found";
}
?>

谢谢你。

Answer 1

简单地，替换这条语句:echo implode("\n", $matches[0]);有了这个:

echo substr(implode("\n", $matches[0]),166,11);