cURL POST字符串的格式

Question

I have seen post data passed to a cURL option in several ways such as an array with key value pairs, as a string like so: "username=user&password=pass" but I came accross a different type of format which appeared odd to me and maybe some of you can clarify this. It looks as follows:

$sPost = "session[username_or_email]=$username&session[password]=$password&return_to_ssl=true&scribe_log=&redirect_after_login=%2F&authenticity_token=$authenticity_token";

curl_setopt($ch, CURLOPT_POSTFIELDS, $sPost);

Why exactly does it look that way "session[username_or_email]"?

Answer 1

Some form processors will treat a POST variable name with square brackets like an associative array. Imagine your post was coming from a form:

<form>
  <input type="hidden" name="session[username_or_email]">
  <input type="hidden" name="session[password]">
</form>

In PHP, for instance, this will be processed as:

$_POST=array(
   'session' => array(
      'username_or_email' => whatever,
      'password' => whatever
   )
)

This is just by convention. As far as the HTTP POST itself, just think of these as two different variable names that happen to contain square brackets.