PHP不解码POST

Question

Is it normal for PHP not to decode $_POST sent as application/x-www-form-urlencoded through AJAX?

I want to use urldecode but it gets rid of my + characters. Help?

:

15:51:55.490[755ms][total 755ms] Status: 200[OK]
POST  Load Flags[LOAD_BYPASS_CACHE  LOAD_BACKGROUND  ] Content Size[72] Mime Type[text/html]
   Request Headers:
      Host[]
      User-Agent[Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.8) Gecko/20100722 Firefox/3.6.8]
      Accept[text/html, */*]
      Accept-Language[en-us,en;q=0.5]
      Accept-Encoding[gzip,deflate]
      Accept-Charset[ISO-8859-1,utf-8;q=0.7,*;q=0.7]
      Keep-Alive[115]
      Proxy-Connection[keep-alive]
      Content-Type[application/x-www-form-urlencoded; charset=UTF-8]
      X-Requested-With[XMLHttpRequest]
      Content-Length[164]
      Pragma[no-cache]
      Cache-Control[no-cache]
   Post Data:
      id[133]
      content[%253Cp%253E%250A%2509Test%2520test%2520-%2520this%2520will%2520disappear%253A%2520%2B%253C%2Fp%253E%250A]
      title[Plus%2520character%2520not%2520working]
   Response Headers:
      Via[1.1 KIGALI]
      Connection[Keep-Alive]
      Proxy-Connection[Keep-Alive]
      Content-Length[72]
      Date[Mon, 02 Aug 2010 03:51:55 GMT]
      Content-Type[text/html; charset=utf-8]
      Server[Apache/2.2.12 (Ubuntu)]
      X-Powered-By[PHP/5.2.10-2ubuntu6.4]
      Vary[Accept-Encoding]
      Keep-Alive[timeout=15, max=100]

Answer 1

Part of urldecode's functionality is to turn + signs into spaces. To get around this, you should urlencode any + signs in your string, so they turn into %2B

So:

<?php
$theTag = 'c++';
urldecode($theTag);
  // output is "c  "
$theTag = urlencode($theTag);
urldecode($theTag);
  // output is "c++"
?>

Now, the superglobals $_GET and $_REQUEST are already decoded. Using urldecode() on an element in $_GET or $_REQUEST could have unexpected and dangerous results. I'm not sure about $_POST. But it well may be decoded too.

---

From your question, I'm not sure exactly what you're dealing with, but looking over the comments on urldecode in the PHP manual, here is a comment you may be interested in:

It's worth pointing out that if you are using AJAX and need to encode strings that are being sent to a PHP application, you may not need to decode them in PHP.

<?php
echo stripslashes(nl2br($_POST['message']));
?>

Will properly output a message sent with the javascript code if the message is encoded:

message = encodeURIComponent(message)

And is sent with an AJAX POST request with the header:

ajaxVar.setRequestHeader('Content-type', 'application/x-www-form-urlencoded')