PHP在表单上重新加载当前页面提交

Question

I have a form on a page to submit a comment, and once a user places a comment I would like it to reload the page.

This is what I got

      $insertGoTo = "employer.php?employer=" . $row_employer_page['employer'] . "";
  if (isset($_SERVER['QUERY_STRING'])) {
    $insertGoTo .= (strpos($insertGoTo, '?')) ? "&" : "?";
    $insertGoTo .= $_SERVER['QUERY_STRING'];
  }
  header(sprintf("Location: %s", $insertGoTo));
}

It works, however I got this error on submit.

    Notice: Undefined variable: row_employer_page in /u/students/m/*******/public_html/cis231/project/employer.php on line 51

Warning: Cannot modify header information - headers already sent by (output started at /u/students/m/*******/public_html/cis231/project/employer.php:51) in /u/students/m/*******/public_html/cis231/project/employer.php on line 56

The lines it references are the code I posted above. I'm not sure what's going on, it reload the page how I want but throws that error

Answer 1

You can not send headers once you've echoed content already (at line 56). That header function. You may want to use a template engine though and echo the compiled template at the end of the file.

Another solution would be to capture the output with http://php.net/manual/de/function.ob-start.php and flush it afterwards.